Porting various applications and games to mobiles phones is something of a holy-grail: the screen is smaller, controls different so the simple answer is, you cannot simply port the application, you need to strip it down, to rethink it completely.
Rymdkapsel is a real-time strategy / building game where you expand your space station by building corridors and rooms, breeding minions, discover monoliths while defending against raiders. The main twist: rooms are shaped like Tetris blocks and dispensed randomly. The game supports rotation of the view and zoom, unit-allocation.
Despite this richness, the game is very playable as the game UI has been stripped down to the minimum: rooms are coloured squares and units are white rectangles, whose height diminishes when they are inactive or hurt. I took me a few seconds to understand how pieces are rotated, but the tutorial is very helpful and non intrusive. The music and the sound effects are well adapted to the overall look of the game.
The game itself is very easy and gets harder and harder, it is also designed to terminate, survive to wave 28, and the game ends. The main challenge seems to reach wave 28 in 45 minutes (I managed in 70). While the game relies heavily on colours, it has a colour blind mode, it supports game center, does not pop-up any ads, in short it behaves like an upstanding app.
Rymdkapsel is the demonstration you can do interesting games on mobile phones that are cross-platform (the game is available on Android, iOS, Playstation Vita, OS X, Linux and Windows). I highly recommend it.