I don't know if Rogue Touch is in depth enough for you but it is a game that I never get bored of. It can take a couple hours if you get a good game but its something that you get better at over time. Plus its always getting great updates. Wolfenstein is really worth it too. Not to mention doom and quake when they arrive.
If it hasn't been mentioned already, get Wolfenstein 3D. I am still playing it 17 years after buying it. You will probably never finish Ms. Pac-Man either (I am starting to think there is no end.) PuzzleQuest seems to be a lengthy one as well.
Wait for Car Jack Streets, you have to pay $50000 every week to pay off $1,000,000, so that's pretty long term. And it's in real time, so if you miss a week in real life, you miss a week in the game.
Here are long-term games on my iPhone Payback Fieldrunners Hero of Sparta Chronicles of Inotia Bike or Die 2 Baseball Superstars 09 Dungeon & Hero Vay Yard Sale Hidden Treasure: Sunnyville Bobby Carrot Forever Reign of Swords The Quest
Sway and Galaxy on Fire. I spend +30 mins on some sway levels! Galaxy o fire is epic!! Think 3D EV Nova.
I'd say Bounce On is worth a look, I put an awful lot of time into getting 100% completion for the 3 current worlds. Plus with the promise of (i think) another 3 worlds to come as free updates, you can't really go wrong.
I think by "long term" he means platformers, judging by the examples he gave, which those two are not. Fieldrunners and Galcon have replay value, but I wouldn't call them long term. Personally, I like Bugdom 2, but that may only be because I used to play the first one on the old Macs in like second grade.
Well I´d suggest getting: -Rolando (Platformer) -Vay (Oldschool-Round-Based-RPG) -Bounce On (Platformer) -Warfare Inc. (Strategy game like C&C) -Dungeon&Hero (Best Action RPG atm I think) -Chronicles Of Inotia: Legend of Feanor (Action RPG) -Hero of Sparta (God of War for the iPod Touch ) -geoDefense (TD-Game which is quite difficult) -Sway (Platformer)
Jailbreak your iPhone, download some emulators, download some ROMs, and voila, a lot of in-depth games. Although the controls and graphics lack substantially from the consoles the games were originally made for.
How Long Can You Press This Button might be the best choice. It lasts as long as you want it to--no limit! And it never gets any less fun than it started (Or on a more serious note, try Enigmo. 50 levels at least, and they get quite challenging. For a TD, consider Elemental Monsters, 7Cities or geoDefense. All have lasted me for many hours and have a lot of depth/complexity.)
Fieldrunners or iDracula. iDracula seriously will keep you playing for a while. Everyone I know (including me) plays it at least like once a day. Oh, or Zombieville USA, but you lose interest after a while because every level is the same.