Hardware Question for app development

Any 15"+ MacBook Pro or midrange iMac would be fine in my opinion.

 

The most important thing is monitor size. Get the biggest monitor you can afford.

 

I got the most low-end MBP there was one year ago and a cheap 24" monitor. You don't need anything else.

 

Almost any Intel Mac, from a used Mini on up, running Snow Leopard. But a big monitor (or two!) really helps.

The other big expense that people miss: you'll need test devices. Lots of them for maximizing the market size for a game app.

From old iPod Touches and maybe a 2G or 3G, to the latest iPad and iPhone 4.

An old 2nd or 3rd gen iPod Touch is almost an absolute requirement, since it's the only device that will allow you to both upgrade to the latest 4.1 beta and then downgrade back down to iOS 4.0 or OS 3.1.x in an officially supported manner.

And an iPhone 2G or 3G or 1st gen iPod Touch are required for performance testing on the slowest devices (400 MHz armv6 CPU, OpenGL ES 1.0 GFX).

The fastest current device is the iPad (1 GHz armv7 CPU, OpenGL ES 2.0 GFX).

You potentially have 3 different native screen resolutions to support as well (320x480, iPad, i4).