communication with android over the Internet

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I'd like to make an app on Android that will receive: -stream video from cameras -map -some other data like velocity, state of program etc.

The app should also send some requests.

Could You help me how can i achieve this? Should I use ROSjava or it won't give me all the needed features? Maybe use websockets?rosbridge ?Or sth else (protocol/technology), especially for video streaming? If u could show me some examples or share some thoughts, it would be nice. Sadly i am new to java/android and network programming.