Ifly is one of of a few apps that support terrain currently (not synthetic vision,yet) for Andriod. I have installed Garmin Pilot (advantage duat weather/flight planning integration, it does e6b calcs for you) Avilution (most streamlined and quick interface) Avare(free!) Naviator (don't care for this one) and Ifly beta.
I use Ifly because it's the best terrain option. Synthetic Vision would be a killer feature outclassing anything else on the Andriod platform currently. I'm looking forward to a non-Beta Ifly (has a few bugs)!
One feature I would like soon is an AGL panel near the terrain profile, that would be a very nice feature in addition to the terrain highlights.