Yeah I built an application as part of a software engineering course this year. It's pretty powerful and fun too.
Powerful my a**, start up Eclipse with ADT and watch it burn your RAM xD starts out with 700MB, leaks so much it builds up like 2GB by the end of the day (needs at least 3-4 restarts over an 8 hour session)... Emulator is slow as hell (and the current HAXM causes both Windows and Mac to go BSOD, so no x86 emulator, unless you install it on VMWare (only tablet OS can be found as x86 iso though)... But both need Hyper-V to be disabled, so no Windows Phone 8 emulator for you while doing that, and Hyper-V hates Android and turning it on and off needs come command line / registry messing and a reboot).
And when it comes to the designer, things sometimes turn out to be extremely awkward, especially if you use a listview or a viewflipper :/
Also there are bugs like Eclipse importing R into your code, making you unable to export the apk. Or like getting a random corruption so you have to backup your entire workspace, delete it, make a new one and import your workspace data.
So, it's a cheap platform, prepare to face the downsides of being cheap -.-
Android Studio looks better, didn't have too much time with it though. But Eclipse is annoying and slow, plus there are other annoying things. From a developer's view, WP and iOS are waaaay better than Android.
So in short, I don't really like it, but I only get Android jobs
There is also a Native Developer Kit for Android and Visual Studio if you want to work with C++.