So I picked up this game on a recommendation from a buddy of mine at work. It's awesome.
It's totally a nerdy programmer game. The whole premise is you get different atoms/molecules and you have to design and build a sort of factory or 'reactor' to create different molecules out of them.
It gets crazy complex. It's available for PC/Mac for like $10. There's also an Android version for $3, but you need a REALLY big screen to be able to play it.
But yeah it's a cheap fun game that'll keep you busy for hours. Definitely worth it IMO. There are videos on youtube of it if you want to take a peek.
It's less about res and more about physical size. I've got a 2.5 x 8" screen on my phone and it's really difficult for me to press where I need to press.
There's a free demo for Android... so you can try that out to see if it'll work on your phone.