Android Developer for messenger

He worked out a messenger, added new different technologies, processed deprecated code.

The following technologies / functions have been added to the project:

Send photos, videos, voice messages, files.
Possibility of sending and showing the geoposition directly from the application.
Capacity to record photos/video directly from the app.
Notification of reading the message.
Adding group chats.
Adding a profile image.
The ability to change the user name directly in the application.
Russianization of the application.
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