I have the Andie Graph TI-83 emulator on my Android device, see
http://www.appbrain.com/app/andie-graph/net.supware.tipro &
https://play.google.com/store/apps/details?id=net.supware.tipro.
Andie Graph cannot load programs from the Android SD-card or import them using the app.
My idea for a new Android app would be to manipulate the file corresponding to the battery backup RAM (ti83.RAM) that is stored in the same directory as the ROM (ti83.rom). This app should be able to import and export programs and data from the RAM-file from/to 83p-files etc. It might be easier to first develop a command-line program that run on an external computer.
I'm not sure if the RAM-file in Andie Graph is just a dump of the actual emulated RAM or if it's a different format. One problem is that Andie Graph is not open source but there is an earlier version for TI-85 that is and I think the RAM is handled in the same way, see
http://dougmelton.com/android/andie-graph/ &
http://fms.komkon.org/ATI85/. I do not know enough about the TI-83 RAM memory map to be able to write this program. I've not yet experimented with RAM-files from other TI-83 emulators.
Is there a way to convert a TI-83 backup-file (backup.83b) to a RAM-file and vice versa?
TI-83 is still sold where I live under the name TI-82 STATS and is very common among highschool students.