Added playback time indicators, implemented as 3 textviews inside a linear layout. Added a helper function to format the text for playback elapsed time as well as total track duration. Added code to onCreate to display these time indicators. Still need to add code so that the playback elapsed time ticks up as the audio is played back or being recorded.
Moved code to obtain pointers to views to the inside of onCreate so that they do not need to be re-obtained in each onClick listener
Added a Runnable which updates the output of the elapsed time during playback ever ~10ms.