5. Android Continues to Rule the OS Market
In 2024 and Android continues to be the most popular
operating software with a 70% market share. This means,
that out of the 8.08 billion global population, more than
3.9 billion own Android phones.
While all this data might not sound shocking to you, the
point we want to make is that – now more than ever,
mobile app development companies need to pay close
attention to what’s trending with Android apps. Look at
the chart below that shows how Android users have
grown over the last decade. It also shows how it’s
expected to touch 4.2 billion users by 2025.
10. Machine Learning and Artificial Intelligence
One of the most significant Android application development trends is
incorporating artificial intelligence and machine learning. These technologies
are being used to create more personalized and intuitive experiences for
users and improve the performance and functionality of applications. For
example, many applications now use machine learning to analyze user data
and make predictions, while others are incorporating chatbots to provide
more efficient customer service.
Video Editor and Maker
Video editing and making is a popular trend in Android app development.
Many video editing and making apps on the Google Play Store allow users to
create, edit, and share videos on their Android devices. These apps typically
include features such as video trimming, merging, adding filters and effects,
and more. Additionally, many apps allow easy sharing on social media
platforms such as YouTube, Instagram, and TikTok.
11. DeepFake Apps
Deepfake technology, which uses machine learning to manipulate video and
audio content, has become a trending topic in recent years. The technology
has advanced significantly, making it possible to create highly realistic deep
fake videos with just a few clicks. As a result, deepfake apps have begun to
appear on the Google Play Store, allowing users to create and share their deep-
fake videos and photos on their Android devices.
HealthCare Apps
Healthcare apps have become a popular trend in Android app development.
These apps can assist users in tracking and managing their health, from
monitoring vital signs to reminding them to take medication. These apps have
a wide range of features, such as:
•Tracking and monitoring fitness and physical activity
•Tracking and logging food and water intake
•Tracking sleep patterns
•Tracking mental and emotional well-being
•Providing reminders for taking medication and scheduling doctor's
appointments
12. The healthcare app development is driven by the increasing adoption of
smartphones and the internet and the need for more convenient and
accessible healthcare services. With the rise of telemedicine, the trend is
expected to continue growing as more people turn to their devices for
healthcare needs.
It's worth noting that while healthcare apps can be a valuable tool in
managing one's health, they are not meant to replace professional medical
advice. It is essential to consult with a healthcare provider before using a
healthcare app and to use it with professional medical guidance.
13. Productivity Apps & Tools
There has been a recent trend toward developing productivity apps
and tools for Android devices. These apps and tools are designed to
help users manage their time more effectively and efficiently. They can
include task management, attendance management, calendar
integration, and note-taking capabilities. Some popular productivity
apps for Android include Todoist, Evernote, and Google Keep.
Additionally, there has been an increase in the use of virtual assistants,
such as Google Assistant, to help users manage their tasks and
schedule.
5G Technology
The emergence of 5G technology has led to new opportunities for
Android app development. 5G networks offer faster speeds and lower
latency than previous generations of cellular networks, allowing more
data to be transmitted in a shorter amount of time. This opens up new
14. Blockchain Technology
Blockchain technology is a decentralized and distributed digital ledger
used to record transactions across a network of computers. The
technology powers cryptocurrencies like Bitcoin and Ethereum but has
many other potential uses, such as supply chain management, voting
systems, etc. Android app development is one area where blockchain
technology is increasingly used as developers look to create
decentralized apps (dApps) that can take advantage of the security and
immutability of blockchain technology. Some popular use cases for
blockchain in Android app development include creating decentralized
marketplaces, digital wallets, and lending platforms.
15. Augmented and Virtual Reality
Augmented and virtual reality are also expected to increase
in 2023. These technologies create more immersive and
engaging user experiences, allowing them to explore
virtual worlds or view products in 3D. This is especially
relevant in the gaming, education, and entertainment
industries.
Foldable Devices
Foldable devices, such as smartphones and tablets with
flexible displays, are a relatively new trend in Android
technology. As more and more of these devices hit the
market, developers are beginning to take notice and adapt
their apps to take advantage of the unique capabilities of
16. Instant Apps
Instant Apps are a relatively new Android app development trend that allows
users to run apps without installing them on their devices. Instead, users can
access the app through a web link, allowing them to try it before committing to
a complete installation.
•Faster Access to Apps
Instant apps allow users to access apps quickly without downloading and
installing them. This can be useful for apps that are only needed occasionally,
such as shopping apps, or for users who need more storage space on their
devices.
•Better Discovery
Instant apps make it easier for users to discover new apps, as they can be
accessed through web links or search engines, increasing an app's visibility and
the chances of being downloaded.
•Increased Conversion Rates
By allowing users to try out an app before committing to a full installation,
instant apps can increase the likelihood that a user will convert to a full
installation. It is beneficial for app developers, as it can lead to increased
17. IoT-Enabled App
IoT (Internet of Things) enabled apps are a growing trend in Android
app development, as they allow for integrating smart devices and
connected appliances into android applications. These apps can
control and monitor many devices, from smart thermostats to
security cameras, and provide users with a more connected and
automated home experience.
•Smart Home Control
IoT-enabled apps allow users to control and monitor a wide range of
smart devices and connected appliances from their devices, such as
lights, thermostats, and security cameras.
•Automation and Personalization
IoT-enabled apps are used to automate specific tasks and
personalize the user experience. For example, users can adjust their
thermostats to their preferred temperature when they arrive home
18. Android vs iOS User Growth
The iOS vs Android supremacy debate has been going on for quite
many years now without a clear winner. iOS dominates in terms of
better updates and support, brand loyalty, eco-system lock-ins, and
security. However, the volume game belongs to Android.
It’s not just because Android phones can cater to a more diverse
market with a wider affordability range. Its open ecosystem,
customization, and flexibility options also make them a great choice
for app developers and businesses.
Let’s not forget how Android phones are popular in the emerging
markets that are just beginning to adopt smartphones. Add seamless
integration with Google services to that, and Android hits the jackpot
of value-added convenience to a very large user base. These users also
need access to Gmail, Google Drive, and Google Maps on a daily basis.
19. Introduction: Mobile Applications
Android is a mobile operating
system developed by Google
and is used by a variety of
devices such as smart phones,
tablets, smart watches, and
20. These apps are built to perform a
wide range of tasks and offer various
functionalities that cater to the needs
of users. Mobile applications have
become an integral part of modern
life, offering convenience,
entertainment, productivity, and
access to information on-the-go.
21. There are two main types of mobile applications based on the
platform they are developed for:
1. Native Mobile Applications: These apps are specifically
developed for a particular mobile operating system (OS) like
Android or iOS, utilizing the programming languages and
development tools native to that platform. Native apps can
take full advantage of the device's hardware and features,
providing optimal performance and user experience. However,
separate development is required for each platform, which
can increase development time and cost.
22. 2. Cross-Platform Mobile Applications: Cross-platform apps
are designed to work on multiple mobile platforms, allowing
developers to write code once and deploy it across different
operating systems. This is achieved using frameworks like
React Native, Flutter, or Xamarin, which enable developers
to create a single codebase that can be used on both
Android and iOS devices. Cross-platform development
reduces development time and costs but may have some
limitations in accessing certain device-specific features.
23. Mobile applications cover a vast array of
categories, including but not limited to:
1. Social networking apps (e.g., Facebook, Twitter,
Instagram)
2. Productivity and utility apps (e.g., Microsoft Office, Ever
note, Google Drive)
3. Entertainment apps (e.g., YouTube, Netflix, Spotify)
4. Gaming apps (e.g., Candy Crush, PUBG Mobile,
Pokémon GO)
5. E-commerce apps (e.g., Amazon, eBay, Alibaba)
6. News and media apps (e.g., CNN, BBC News, The New
York Times)
7. Health and fitness apps (e.g., Fitbit, MyFitnessPal,
30. Version Code name API Level
Code name Version numbers API level Release date
No
codename
1.0 1 September 23, 2008
No
codename
1.1 2 February 9, 2009
Cupcake 1.5 3 April 27, 2009
Donut 1.6 4 September 15, 2009
Eclair 2.0 - 2.1 5 - 7 October 26, 2009
Froyo 2.2 - 2.2.3 8 May 20, 2010
Gingerbread 2.3 - 2.3.7 9 - 10 December 6, 2010
Honeycomb 3.0 - 3.2.6 11 - 13 February 22, 2011
Ice Cream
Sandwich
4.0 - 4.0.4 14 - 15 October 18, 2011
Jelly Bean 4.1 - 4.3.1 16 - 18 July 9, 2012
KitKat 4.4 - 4.4.4 19 - 20 October 31, 2013
Lollipop 5.0 - 5.1.1 21- 22 November 12, 2014
Marshmallow 6.0 - 6.0.1 23 October 5, 2015
32. 1. Empty Activity: This is the simplest default activity. It creates a blank
screen with a basic layout file and a corresponding Java/Kotlin class.
You can start building your app from scratch with this option.
2. Basic Activity: The Basic Activity template includes a pre-designed
layout with an action bar (toolbar) at the top. It also comes with some
basic functionalities like a floating action button (FAB) and a
navigation drawer.
3. Bottom Navigation Activity: This template provides an app with a
bottom navigation bar, allowing users to navigate between different app
sections or tabs.
4. Tabbed Activity: This template includes a tab layout that allows you to
organize your app's content into tabs, making it easy for users to switch
between different sections.
33. 5. Master/Detail Flow: This template is suitable for apps that need to
display a list of items and their details. It creates a master list view
and a detail view for each item.
6. Full screen Activity: The Full screen Activity template creates an
activity that displays content in full screen mode, hiding the system UI
elements (status bar and navigation bar) until the user interacts with
the screen.
7. Login Activity: This template provides a basic login screen with fields
for username and password. It is a good starting point for apps that
require user authentication.
8. Maps Activity: If your app involves displaying maps and location-
based services, this template sets up a map fragment and includes
some basic map functionalities.
38. Linux kernel
It is the heart of android architecture that exists at the root of android
architecture. Linux kernel is responsible for device drivers, power
management, memory management, device management and resource
access.
Bottom layer of android operating system is Linux kernel. Android is built
on top of Linux 2.6 Kernel and few architectural changes made by Google.
Linux Kernel provides the basic system functionality such as process
management, memory management and device management like
camera, keypad, display etc. It also provides array of device drivers which
makes interfacing the android with peripheral hardware easy.
39. Library Explanation
SQLite This library is used to access data published by content providers and
includes SQLite database management classes
SSL This is used to provide internet security
OpenGL OpenGL is used to provide Java interface to the OpenGL/ES 3D graphics
rendering API.
Media framework It is used to provides different media codecs which allow the recording and
playback of different media formats
WebKit It is the browser engine used to display internet content or HTML content
Web browser Based on the open-source WebKit layout engine, coupled with Chrome’s V8
JavaScript engine supporting HTML5 and CSS3.
Libraries
On the top of Linux Kernel another layer called libraries is present. It provides the different libraries useful for
well functioning of android operating system.
Libraries are java libraries build specific for android operating system. Some of important libraries are
40. It is the third component of the android architecture and placed in second
layer from bottom. It provides most important part of android called
Dalvik Virtual Machine.
Dalvik Virtual Machine is similar to Java Virtual Machine (JVM) but only
difference is that it is designed and optimized for Android.
Dalvik Virtual machine uses core functions of Linux such as memory
management and multi threading and enables each android app to run
its own process.
The Android runtime also provides a set of core libraries which enable
Android application developers to write Android applications using
standard Java programming language.
41. Platform libraries
The Platform Libraries includes various C/C++ core libraries and Java based
libraries such as Media, Graphics, Surface Manager, OpenGL etc. to provide a
support for android development.
•Media library provides support to play and record an audio and video
formats.
•Surface manager responsible for managing access to the display
subsystem.
•SGL and OpenGL both cross-language, cross-platform application program
interface (API) are used for 2D and 3D computer graphics.
•SQLite provides database support and FreeType provides font support.
•Web-Kit This open source web browser engine provides all the functionality
to display web content and to simplify page loading.
•SSL (Secure Sockets Layer) is security technology to establish an encrypted
link between a web server and a web browser.
42. SGL stands for "Scalable Graphics Library" and is the graphics
subsystem used by Android. SGL is the low-level graphics library
implemented in native code that handles rendering.
The Secure Sockets Layer (SSL)—now technically known as
Transport Layer Security (TLS)—is a common building block for
encrypted communications between clients and servers.
46. Application framework
It is fourth component in android operating system stack.
Android applications directly interacts with application
framework. Application framework manages the basic
functions of android device such as resource
management, voice call management etc.
Application Framework layer provides many higher-level
services to applications in the form of Java classes.
Application developers are allowed to make use of these
services in their applications. The important blocks of
47. AP Block Explanation
Activity Manager Used to manage complete activity life
cycle of applications
Content Providers Used to manage the data sharing
between two applications
Telephony Manager Used to manages all voice calls
Location Manager Used to manage the Locations obtained
using GPS or cell tower
Resource Manager Used to manage the different types of
resources used in android app
48. Applications
Android application is the fifth component of android OS
and situated at the top layer. Applications
are developed to be installed on this layer only.
Examples of such applications are Contacts Books,
Browser, Games, etc.
56. Android Resources Organizing &
Accessing
There are many more items which you use to build a good Android application.
Apart from coding for the application, you take care of various
other resources like static content that your code uses, such as bitmaps,
colors, layout definitions, user interface strings, animation instructions, and
more.
These resources are always maintained separately in various sub-directories
under res/ directory of the project.
This tutorial will explain you how you can organize your application resources,
specify alternative resources and access them in your applications.
57. Sr.No. Directory & Resource Type
1 anim/
XML files that define property animations. They are saved in res/anim/ folder and accessed from
the R.anim class.
2 color/
XML files that define a state list of colors. They are saved in res/color/ and accessed from
the R.color class.
3 drawable/
Image files like .png, .jpg, .gif or XML files that are compiled into bitmaps, state lists, shapes,
animation drawable. They are saved in res/drawable/ and accessed from the R.drawable class.
4 layout/
XML files that define a user interface layout. They are saved in res/layout/ and accessed from
the R.layout class.
5 menu/
XML files that define application menus, such as an Options Menu, Context Menu, or Sub Menu.
They are saved in res/menu/ and accessed from the R.menu class.
58. 6 raw/
Arbitrary files to save in their raw form. You need to
call Resources.openRawResource() with the resource ID, which
is R.raw.filename to open such raw files.
7 values/
XML files that contain simple values, such as strings, integers, and colors. For
example, here are some filename conventions for resources you can create in this
directory −
•arrays.xml for resource arrays, and accessed from the R.array class.
•integers.xml for resource integers, and accessed from the R.integer class.
•bools.xml for resource boolean, and accessed from the R.bool class.
•colors.xml for color values, and accessed from the R.color class.
•dimens.xml for dimension values, and accessed from the R.dimen class.
•strings.xml for string values, and accessed from the R.string class.
•styles.xml for styles, and accessed from the R.style class.
8 xml/
Arbitrary XML files that can be read at runtime by calling Resources.getXML().
You can save various configuration files here which will be used at run time.
59. Alternative Resources
Your application should provide alternative resources to
support specific device configurations.
For example, you should include alternative drawable
resources ( i.e.images ) for different screen resolution and
alternative string resources for different languages.
At runtime, Android detects the current device configuration
and loads the appropriate resources for your application.
60. Application Model
In Android, an application model refers to the way in which applications are designed, developed, and
deployed on the platform. The Android application model is based on the principles of modularity,
security, and flexibility.
The key components of the Android application model include:
•Activities: Activities are the building blocks of Android applications. They represent individual
screens or user interfaces within an application.
•Services: Services are components that run in the background and perform long-running operations or
provide functionality to other applications.
•Broadcast Receivers: Broadcast receivers are components that listen for system events or broadcasts
and allow applications to respond to them.
•Content Providers: Content providers are components that allow applications to share data with
other applications.
•Intents: Intents are messages that are sent between components within an application or between
different applications.
61. The Android application model also includes a set of APIs and
frameworks that developers can use to create rich, engaging
applications. Some of these include:
• User Interface Framework: This framework provides developers
with tools to create interactive user interfaces for their
applications.
• Application Framework: This framework provides developers
with access to system-level functionality and services, such as
the camera, sensors, and location services.
• Storage Framework: This framework provides developers with
tools to store and retrieve data from various types of storage,
such as databases, files, and shared preferences.
62. Infrastructure and Managing Resources
Infrastructure and resource management are essential aspects of building robust
and efficient Android applications. Here are some key considerations for managing
resources and infrastructure in Android:
•Memory Management: Android applications run on devices with limited memory
and resources. It is essential to manage memory efficiently to ensure smooth
performance and avoid application crashes. Android provides a garbage collector
that automatically frees up memory by removing objects that are no longer in use.
However, it is also essential to release resources such as files, database
connections, and network connections when they are no longer required.
•Network Management: Android applications typically rely on network
connections to communicate with servers and fetch data. To manage network
connections effectively, it is important to use Android's network APIs, which
include HTTP, HTTPS, and WebSocket protocols. It is also essential to handle errors
and network connectivity issues gracefully, such as retrying failed requests and
displaying appropriate error messages.
63. •User Interface Management: Android provides a variety of UI
components such as buttons, text fields, and lists. It is important to
design the UI efficiently to ensure a smooth user experience. Some
best practices for UI management include using the appropriate UI
components, optimizing the layout of UI elements, and providing
responsive feedback to user actions.
•Battery Management: Android devices rely on battery power, and
it is important to manage power consumption efficiently to avoid
draining the battery too quickly. Some best practices for battery
management include minimizing network usage, avoiding CPU-
intensive operations, and using Android's power-saving features
such as Doze mode and App Standby mode.
64. •Storage Management: Android applications may
need to store data on the device, such as files,
images, and user preferences. It is important to
manage storage efficiently to avoid running out of
space and causing performance issues. Some best
practices for storage management include using
Android's storage APIs, compressing files and
images, and removing unused files and data
regularly.
66. There are many frameworks and tools available for developing
Android applications. Here are some popular ones:
•Android Studio: Android Studio is the official integrated
development environment (IDE) for Android development. It
includes features such as code editing, debugging, and
performance profiling tools.
•Java: Java is the official programming language for Android
development. Android Studio provides support for coding in Java.
•Kotlin: Kotlin is a modern programming language that is gaining
popularity among Android developers due to its concise syntax
and improved readability.
67. •Gradle: Gradle is a build automation tool that is used to manage
dependencies and build Android projects. Android Studio uses
Gradle to build, test, and deploy Android apps.
•Android SDK: The Android Software Development Kit (SDK)
provides tools and APIs for Android development. It includes a
range of libraries and tools for developing Android apps.
•Retrofit: Retrofit is a REST client library for Android that simplifies
the process of making network requests and handling responses.
•Glide: Glide is an image loading and caching library for Android
that provides smooth scrolling and efficient memory usage.
68. •Firebase: Firebase is a backend-as-a-service (BaaS) platform that
provides a range of tools for building and managing Android apps. It
includes features such as authentication, real-time database, and
cloud messaging.
•Room: Room is a persistence library for Android that provides an
abstraction layer over SQLite. It simplifies the process of working with
databases in Android apps.
•ButterKnife: ButterKnife is a view binding library for Android that
simplifies the process of binding views and setting listeners. It helps
reduce boilerplate code in Android apps.
70. In Android, a profile is a collection of settings and configurations that are
specific to a particular user or scenario.
Profiles allow users to customize their device to suit their needs and preferences,
and to switch between different configurations depending on the situation.
There are several types of profiles in Android, including:
•User profiles: User profiles allow multiple users to share a single device while
maintaining their own personalized settings, preferences, and data. Each user has
their own profile, which can be accessed by logging in with their own credentials.
•Work profiles: Work profiles allow users to separate their work and personal
data on a single device. Work profiles are managed by an organization's IT
department and provide a secure environment for work-related apps and data.
71. Device owner profiles: Device owner profiles are used by
organizations to manage devices that are used exclusively
for work purposes. Device owner profiles give organizations
complete control over the device and its settings.
Guest profiles: Guest profiles are temporary profiles that
can be created for visitors or other temporary users of the
device. Guest profiles provide a limited set of features and
settings and do not save any user data.
73. Designing an application for Android involves several important steps to ensure
that the app is user-friendly, visually appealing, and functional. Here are some
key steps in the application design process for Android:
•Define the purpose and scope of the application: Before starting the design
process, it's important to have a clear understanding of the purpose and scope of
the app. This includes identifying the target audience, the features and functions
that the app will provide, and the overall user experience.
•Sketch out the app's layout and structure: Once you have a clear understanding
of the purpose and scope of the app, you can begin to sketch out the layout and
structure of the app. This involves creating wireframes or mockups that show the
different screens and features of the app.
74. •Choose a design theme and color scheme: Choosing a design theme and color
scheme is an important step in creating a visually appealing app. This involves
selecting a color palette and design elements that will help to convey the app's
purpose and brand identity.
•Design the user interface: The user interface (UI) is the visual aspect of the app
that users interact with. This includes the layout of the app's screens, the
placement of buttons and other interactive elements, and the use of icons and
other visual cues.
•Develop the app's functionality: Once the UI has been designed, the next step is
to develop the app's functionality. This involves writing the code that will enable
the app to perform its various functions, such as displaying content, processing
user input, and communicating with other devices or services.
75. •Test and refine the app: Testing is a critical step in the application
design process. This involves testing the app on a variety of devices
and platforms to ensure that it works correctly and meets the
needs of the target audience. Refinement may be necessary to fix
bugs, improve performance, and optimize the user experience.
•Launch and promote the app: Once the app has been tested and
refined, it's time to launch it to the public. This involves submitting
the app to the Google Play Store or other app marketplaces and
promoting it through various marketing channels. Ongoing
maintenance and updates may be necessary to ensure that the app
continues to meet the needs of its users.
77. Memory management in Android is an important aspect of the
operating system that helps to ensure optimal performance and
stability of the device. Android is designed to manage memory
efficiently and effectively through several key mechanisms.
•Memory Allocation: When an application is launched, the Android
system allocates a fixed amount of memory to it. This memory is
used by the application to store data and execute code. If the
application requires more memory than is allocated, the system may
terminate it.
•Garbage Collection: As applications run, they create objects in
memory. Some of these objects are no longer needed and become
garbage. The Android system periodically performs garbage
collection to reclaim memory that is no longer in use.
78. •Low Memory Management: If the device runs low on memory, the
Android system will begin to aggressively reclaim memory from
running applications. This can cause some applications to become
unstable or even crash.
•Memory Leaks: Memory leaks occur when an application fails to
release memory that is no longer needed. This can cause the device
to run out of memory and become unstable. Android provides tools
to help developers identify and fix memory leaks.
•Large Heap Support: Android supports large heap sizes for devices
with more memory, allowing applications to allocate more memory
and run more efficiently.
79. •Caching and Pre fetching: Android uses caching and prefetching to improve
performance and reduce memory usage. Caching allows frequently accessed
data to be stored in memory for quick access, while prefetching loads data into
memory before it is needed to reduce load times.
81. Designing Android applications for limited memory requires careful
consideration of how resources are allocated and managed. Here
are some design patterns that can help you optimize memory usage
in your Android app:
•Use the Flyweight pattern: This pattern is useful when you need to
create a large number of objects that have similar properties.
Rather than creating a new object for each instance, you can reuse
objects by sharing them among instances. This can reduce memory
usage and improve performance.
•Implement the Singleton pattern: This pattern ensures that only
one instance of an object is created and used throughout the
application. This can be useful for objects that are used frequently
or that consume a lot of memory.
82. •Use the Object Pool pattern: This pattern involves creating a pool
of pre-allocated objects that can be reused as needed. This can be
useful for objects that are expensive to create or that are used
frequently.
•Implement the Lazy Initialization pattern: This pattern involves
deferring the creation of an object until it is actually needed. This
can be useful for objects that are expensive to create or that may
not be needed in every execution path.
•Use the Builder pattern: This pattern allows you to create complex
objects by breaking down the construction process into smaller
steps. This can help you avoid creating unnecessary objects or data
structures, which can help reduce memory usage.
83. •Implement the Observer pattern: This pattern allows
you to notify interested objects of changes to another
object. This can help you avoid creating unnecessary
objects or data structures to track changes.
•Use the Iterator pattern: This pattern allows you to
iterate over a collection of objects without having to
create a separate data structure to hold the objects.
This can help reduce memory usage by avoiding the
need to create a large data structure to hold all the
objects.
91. Designing Android applications for limited memory requires careful
consideration of how resources are allocated and managed. Here are
some design patterns that can help you optimize memory usage in
your Android app:
•Use the Flyweight pattern: This pattern is useful when you need to
create a large number of objects that have similar properties. Rather
than creating a new object for each instance, you can reuse objects
by sharing them among instances. This can reduce memory usage
and improve performance.
•Implement the Singleton pattern: This pattern ensures that only
one instance of an object is created and used throughout the
application. This can be useful for objects that are used frequently or
that consume a lot of memory.
92. •Use the Object Pool pattern: This pattern involves creating a pool
of pre-allocated objects that can be reused as needed. This can be
useful for objects that are expensive to create or that are used
frequently.
•Implement the Lazy Initialization pattern: This pattern involves
deferring the creation of an object until it is actually needed. This
can be useful for objects that are expensive to create or that may
not be needed in every execution path.
•Use the Builder pattern: This pattern allows you to create complex
objects by breaking down the construction process into smaller
steps. This can help you avoid creating unnecessary objects or data
structures, which can help reduce memory usage.
93. •Implement the Observer pattern: This pattern allows
you to notify interested objects of changes to another
object. This can help you avoid creating unnecessary
objects or data structures to track changes.
•Use the Iterator pattern: This pattern allows you to
iterate over a collection of objects without having to
create a separate data structure to hold the objects. This
can help reduce memory usage by avoiding the need to
create a large data structure to hold all the objects.
95. The workflow for application development in Android generally
involves the following steps:
•Idea Generation: The first step is to generate an idea for the
application. This can be done by researching the market, identifying
user needs, and analyzing existing applications.
•Planning: Once the idea is generated, the next step is to plan the
application. This involves identifying the features, functionalities,
and user interface of the application. It also involves creating
wireframes and mockups to visualize the application.
•Design: The design phase involves creating the visual design of the
application. This includes creating a style guide, selecting colors,
fonts, and images, and creating the user interface design.
96. •Development: The development phase involves writing the code for
the application. This includes creating the front-end and back-end of
the application, integrating APIs, and testing the code.
•Testing: Once the application is developed, it needs to be tested
thoroughly to ensure that it is free from bugs and errors. Testing can
be done manually or through automated testing tools.
•Deployment: After the application is tested, it is ready to be
deployed to the Google Play Store. This involves creating an account
on the Google Play Store, uploading the application, and submitting it
for review.
•Maintenance: Once the application is deployed, it needs to be
maintained and updated regularly. This involves fixing bugs, adding
new features, and improving the user experience.
98. When it comes to composing applications in Android, there are
several techniques and best practices that developers can follow
to create high-quality, efficient, and maintainable code. Here are
some of the key techniques:
•Model-View-Controller (MVC) architecture: One of the most
common and widely used architectures for Android app
development is the MVC architecture. This approach separates the
application into three components: the model (data and business
logic), the view (user interface), and the controller (handles user
input and coordinates communication between the model and
view).
99. •Model-View-ViewModel (MVVM) architecture: Another popular
architecture for Android app development is the MVVM architecture. This
approach separates the application into three components: the model (data
and business logic), the view (user interface), and the view model (acts as
an intermediary between the model and view, providing data to the view
and handling user input).
•Clean Architecture: This architecture separates the application into
multiple layers, each with a specific responsibility, and each dependent only
on the layers below it. This approach makes the code more modular,
testable, and maintainable.
•Reactive Programming: Reactive programming is a programming paradigm
that focuses on data streams and the propagation of changes. In Android
app development, this can be implemented using frameworks such as
RxJava and RxAndroid.
100. •Dependency Injection: Dependency injection is a technique for providing
objects with their dependencies without creating them directly. This can help to
make the code more modular, testable, and maintainable.
•Kotlin Coroutines: Kotlin Coroutines are a concurrency framework for Android
app development that makes it easier to write asynchronous code. Coroutines
provide a simpler and more intuitive way to write asynchronous code than
traditional threading models.
•Data Binding: Data binding is a technique for binding data directly to views in
the user interface. This can help to simplify the code and make it more efficient.
•Jetpack Components: Jetpack is a set of libraries, tools, and guidance for
Android app development that provides a standardized set of components for
common tasks, such as navigation, data storage, and user interface design.
102. Dynamic linking in Android is a process of linking libraries or other executable
code to an Android application at runtime, rather than at compile time. This
allows for smaller and more efficient APK sizes, as well as the ability to update
libraries independently of the application.
•When an Android application is compiled, it includes references to external
libraries or modules that it depends on. These references are typically resolved
at compile time, resulting in a larger APK file size. With dynamic linking, these
references are instead resolved at runtime, allowing for smaller APK files and
reducing the application's memory footprint.
•The Android operating system provides a dynamic linker called "linker" which
is responsible for linking shared libraries at runtime. The linker loads the
necessary shared libraries into memory and resolves symbols referenced by the
application. This process is transparent to the application and occurs
automatically when the application is launched.
103. Android also supports the use of the Native
Development Kit (NDK) to build and link
native code libraries. NDK provides a set of
tools and libraries to develop C and C++
code for Android, which can be compiled into
shared libraries and linked dynamically to the
Android application at runtime
105. DLLs (Dynamic Link Libraries) are not commonly used in Android
development, as Android uses a different architecture from
desktop operating systems like Windows. Instead, Android uses
a modified version of the Java programming language, which
relies on Java Archive (JAR) files to package and distribute code.
However, there are some cases where you might want to use
DLLs in Android development, such as when you're porting code
from a desktop application or working with a third-party library
that uses DLLs. Here are some tips and rules of thumb for using
DLLs in Android:
106. •Use the Android NDK: The Android NDK (Native Development Kit) is a set of tools
that allow you to develop native applications for Android using C and C++. The NDK
includes support for loading DLLs, which can be useful if you need to port code
from a desktop application or work with a third-party library that uses DLLs.
•Use a cross-platform library: Instead of using a DLL, you might consider using a
cross-platform library that works on both desktop and mobile platforms. Examples
include Boost (a collection of libraries for C++), Xamarin (a platform for building
native apps for iOS, Android, and Windows using C#), and Qt (a cross-platform
development framework for C++).
•Be aware of compatibility issues: DLLs compiled for desktop operating systems
may not work on Android, as Android uses a different architecture and API. Make
sure to test any DLLs thoroughly before using them in an Android project.
107. •Use a wrapper library: If you need to use a DLL in your Android
project, you might consider creating a wrapper library that exposes
the DLL's functionality using a cross-platform API. This can help to
abstract away platform-specific details and make the code more
portable.
•Follow best practices for security: When using DLLs in your Android
project, it's important to follow best practices for security. For
example, you should only load DLLs from trusted sources, and you
should make sure to validate any user input before passing it to the
DLL.
