The document discusses instant messaging apps in Indonesia. It provides information on major messaging apps like Kakao Talk, LINE, Skype and Viber. It analyzes their key features such as texting, voice/video calls, group chats and multimedia sharing capabilities. The document also examines the mobile platforms supported by these apps and reviews their usage in Indonesia, finding that the majority of smartphone users access instant messaging daily and it is their most common online activity. WhatsApp, BlackBerry Messenger, and LINE are identified as the most widely used social messaging apps in the country.