This is my first Android app, and I didn't touch Java in many years. So, first impressions.
I forgot how insanely wordy Java is. And doing anything takes effort, with all the factories, accessors, and whatnot.
I like checked exceptions. Too bad Python doesn't have them (probably impossible by the very nature of a dynamic language, but I've been bitten by an unexpected exception floating up from the depth of the stack before).
Android docs are excellent and one almost never needs to search for answers. Unfortunately, I managed to step into one such case: the so-called "Up" navigation. My chosen API level is 11. The contemporary docs explain how to emulate "Up" using compatibility libraries for APIs before mine, and explain how to use onNavigateUp(), that comes in API level 16. But there's absolutely nothing, nowhere, that tells how do it in API 11. I was walking in circles for days. The answer is actually a secret ID namespace, particularly android.R.id.home. I would never figure it out if not for random pieces of code on the Internet. Good grief, Google. So close to perfect marks.
Oh, and one more thing: Googlers score good sanity points for reimplementing a stock Java API for HTTP (HttpURLConnection and friends). They could've easily rolled their own, but they didn't. They wrote their own runtime, but it's fully compatible with Oracle, including dark corners of SSL. It permits to mostly debug difficult parts on a Linux box. Very nice. Just to see what it could be otherwise, look at their gratiously incompatible Base64.
UPDATE: I forgot to mention that I started with Eclipse, but it was entirely unusable due to crashing all the time (about once an hour, for no discernable reason). I was at Fedora 20 at the time. So, I used command-line tools, and that worked like a charm. There's a Makefile in blitz2 repo linked above.