Anyone familiar with developing software for Android 5.0?

As some of you know, we used to have an Android app for the TRP-sieve application. We took it out of production when we discovered it wasn't working.

The original developer abandoned the app, and none of the usual suspects who write software around here had any experience with Android and wanted to pick up the project.

That last part is probably still true -- nobody here has any experience with Android. But earlier this year I picked up several latest-gen Amazon Fire tablets (on sale for $40). How bad can a tablet possibly be to not be worth $40, right? They're actually pretty nice, to tell the truth, as long as you don't mind being locked into Amazon's ecosystem (or go through some digital gymnastics to get to the Google app store.)

Unfortunately, these tablets run Android 5.0, and BONIC didn't run on 5.0, so I couldn't use it as a development platform to try to debug the long-dead sieve app. That was Februrary.

The good folks at Berkeley have updated BOINC so it runs on Android 5.0. As I type this, I'm running some Einstein apps on my Fire tablet, so I'm pretty darn certain it's able to run BOINC right now.

Which means I can take a look at that sieve app, update it to Android 5.0, and hopefully figure out what's wrong and fix it.

Is there anyone out there familiar with developing for Android? My first question is what development platform do I need? That's pretty easy to answer, but the next question maybe isn't. What I really would like is some information on what it takes to create an app that's compatible with Android 5.0, and whether it's possible to create apps that are compatible with multiple versions of Android.

Any help would be appreciated.
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