Android Application Developeing_FSK data transfer through Audio Jack

I need an android app, which can send and receive FSK data through audio jack. It needs to have the following features: 1- Android app should be able to send and receive FSK data through audio jack,,,there should be to text box ,,one for writhing send data and one to show receive data. 2- There should be three buttons,,,1 for recording,,1 for stop recording and one for play 3- There should be the possibility for start and stop recording through FSK. For example when the application receive #hi> it shoud start recording (disable recording button and enable stop) and when it recive #by> it should stop recording and save it in the storage (enable recording button and play button). 4- When I press play button it should start play the recording 5- I may want to add other command to it, that would be good to have option to add other comment for other application