I can see the confused look on your face already, wondering what the heck a "high score obtainer" is. These are the games that have only one goal, and that is for you to obtain a high score. Sure, most games have some sort of score system built in, but there are only a select few that make you click on that darn OpenFeint button every time you lose. Here are my four favorites.
To me, the best high score games are the ones that keep things the most simple. Ninjump really doesn't have a whole lot going on, just a ninja with an insatiable desire to go up. The controls are as simple as possible, with just a tap sending you to the opposite wall, which is hopefully not occupied by a rival ninja, a building overhang, or a swooping bird. Anything in the middle is gravy though (or maybe chop suey would work better), because your ninja instantly kills anything he touches while in mid air. What's great though is that the game provides a simple twist to the genre, giving you a crazy boost up the screen when you destroy three of the same object in a row.
The best part about the game though is that your score is simply based on how high you get. There are no bonuses and no combos, so you know exactly how hard the person at #1 worked for their score.
There's just something very freeing about Solipskier, and it keeps sucking me in for more. I absolutely love seeing how fast I can get going and how far I can get without falling into the dreaded pit of shame and the game over screen. Like any good game in the "high score obtainer" genre, the controls are incredibly simple, but in this particular instance, difficult to master.
Fastar! is a great high score obtainer that gives you so much more than the average game in the genre. Instead of just giving you one thing to control, Fastar! gives you spells and a sword for your mission to dispatch the enemies with as much haste as possible. Most of the 24 game modes have a simple objective, get through them as fast as possible without dying, and nothing more. Once your level is done, and they will be done fast, the game throws your lowly high score in your face, almost taunting you into playing again.
If you haven't put at least an hour into trying to beat some high score in Fastar!, you must not have a competitive bone in your body.
It's a tough call, but Orbital is probably in my top 5 favorite iPhone games of all time. It has a fairly simple concept that is extremely difficult to master, and is extremely unforgiving. Make one mistake and you are dead, but at least you know exactly what you did when you made the mistake. Also, unlike the rest of the high score obtainers on the list, time is not an issue in Orbital. Take as much time as you'd like... the game doesn't care one bit. Nothing is moving and nothing is growing, it's all you and your increasing incompetence.
The best part of it all is the frustrating realization that your last move may have doomed your game for good. Instead of rushing you past your mistakes, forcing you to mentally move on, Orbital gives you time to scowl at the screen for as long as you want. Nothing is funnier than seeing someone yell at you iPhone after not beating your high score.