My fav is teslar wars.
Plants vs. Zombies HD - my favorite game on any platform in a long time
Angry Birds HD
Spider: Secret of Bryce Manor HD
Flight Control HD
Probably biased cuz I made it, but it's true, my favorite is Red Card Rampage!
World at wars , guitar hero and angry birds ^^ i have only 3
10 limit is a little artificial so I could have also include in my list: Trundle HD, AirAttack HD, Modern Conflict, Aerox, Dark Nebula 2, Call of Atlantis, Enchanted Forest, Ricochet Infinity, Bounce On 2, Soosiz HD, Doodle Sky HD, Spider The Secret of Bryce Manor, Freaking Inkies HD, Dungeon Solitaire, Osmos, Tesserae HD, ESPGaluda 2, Expedition Beyond the Walls, Chop Chop Soccer HD, Meekoo, Crystal cave, Marple, Storm Attack, Everlands HD, Galcon Fusion, Jet Car Stunts, Snail Mail, Rimelands Hammer of Thor, ...
- Ynth (Amazing action puzzle, Beyond Ynth recent release made me discover the original, Beyond is perhaps a better choice but I haven't yet played it)
- Knights of the Phantom Castle (Difficult but great, a sort of Syndicate with a Fantasy background, and not exactly the same budget level)
- Spirit HD (Great action game, learning curve is a bit rude)
- Somersault (Great original platform game)
- Orions: Legends of Wizard (Great Strategy RPG Card game)
- Block Breaker Deluxe 2 (The best brick breaker)
- R Type (Oldie shmup but great, a bit too difficult but worth the sweat)
- Despicable Me: Minion Mania HD (Great puzzle platform game)
- Knight Defense HD (Original and very fun mix of TD, action and strategy)
- Stranded Mysteries of Time & Dracula the Path of the Dragon HD (Two very good adventure games for different reason and different genres)
I don't have a slew of games yet, so thanks for the suggestions. I've found a few websites and the FreeAppADay app that tell you what particular apps are free that day and that has led to me finding a few gems.
Below are a few that I've come to really enjoy.
The Treasures of Montezuma
If you like Bejeweled matching games, just get this now. I can't stop playing.
Galaxy on Fire
Reminiscent of the Wing Commander games from the 90's.
It's like Asteroids with a tilt.
Beautiful Zombie defense game (not like TD)
Virtual Table Tennis
It's an iPod game, but plays well on the iPad. Very addictive.
It's effing Air Hockey!
Has a lot of two player board games