The document describes the HTTP API for connecting a third party application to the GTS-Cloud Mobile Messaging Platform. It allows applications to:
1. Send SMS messages (SMS-MT) to mobile phones by making HTTP requests with message details.
2. Receive SMS messages (SMS-MO) sent from mobile phones through HTTP requests to the application's server.
3. Get delivery reports for sent messages through HTTP requests with message IDs.
4. Check the account balance and details by making HTTP requests with login credentials.
Detailed explanations and samples are provided for making HTTP requests to submit, receive, and get status of SMS messages and accounts.