Back in the deep dark past (2004-2007) I worked on a 3D game for phones of that era (before iphone, android). I recently found some of the test files for the engine, here are some videos.
Very low poly racetrack
The ubiquitous cube
Spacekid in the spacestation corridors
Our Mascot wanders the corridors .. you can't look too far ahead, to keep things really low, which means popup is a little...severe.
Movement is a better in reality - the capture has made the movement a bit jerky.
Dire Straits
Obviously we didn't make this, but it heavily inspired our 3D engine ... textures were just too slow, so we aimed for this look.