these are always hard to answer but some of my favs or must haves are digital clock, agenda widget, batterytime, apps organizer, weatherbug, and Dolphin HD or mini. These are just a few of the apps i usually 'have' to have. As for games well none of them are great for me and idk why angrybirds is so cool, just a boring game i have played different variations before. and if you into music well a recent app that came out, at least to my knowledge, called poweramp is a must have for music. Its 5 bucks though so up to you. Rockplayer for videos for many file types. There tons of apps out there you just got to search for things you might need and then try out various ones that do the same thing and you will eventually find the ones that meet your needs.