I toyed with creating an android game in unity last year, but the cost of the licence ($400) put me off and I ended up doing it natively using java and eclipse (which was fairly painful)
I'm going to give unity another look in, but the unity servers seem pretty well hammered at this point!
One of the reasons I never bought a license was the cost. I followed a Unity course over two months and wanted to develop mobile games. I had the skill to, but committing $400 to something I'd never really done before was insane.
The Apple developer license, Corona/Gamesalad, etc. are far more affordable and less risky. I'm not even sure if you had access to the iOS/Android API without purchasing a license, so I guess you wouldn't be able to practice it.
I'm going to give unity another look in, but the unity servers seem pretty well hammered at this point!