If you've been wholly absorbed by the Mass Effect universe lately, the newly-released "Datapad" should be up your alley. The Universal app--compatible with iPhone, iPad, and iPod Touch--will give you access to codex entries from across the entire Mass Effect trilogy. You'll also be able to access "breaking news" from BioWare and the Alliance News Network, as well as messages from characters in Mass Effect 3 after you interact with them in the game.
The free app (available here) also includes wallpapers you can use you on your iDevice.
A bonus mini-game included with the app--"Fleet Commander"--will also increase your Mass Effect 3 Galactic Readiness Rating by deploying fleets of ships. However, Touch Arcade points out that the mini-game adds "about 0.90% to your galactic rating every four hours," which all things considered, is "not very rewarding."