which mac for photography

I'd go with the Macbook Pro. It's faster and more upgradeable than the Macbook Air, and believe me, you'll need to upgrade the RAM at some point, on the Air the RAM is soldered to the logic board.

Video cards are basically the same but the ones on the Pro run faster. On a side note, macbook air models run hotter but nothing uncomfortable.

In the end both can do the task, the pro is better suited unless you really need the low weight and portability.

How you choose a model computer depends entirely on your priorities of the features of the different devices. Every model makes compromises in order to promote its strengths.

The MacBook Air's strength above all others is portability.In your post yo don't mention size, weight, or portability as something you would consider the Air to achieve. Your priorities, as explained, center around the primary applicability to your interest, being photography. Whether that includes a desire to carry the computer when actually taking photographs, is the only question here. As Chris indicated, for every other possible reason the MacBook Pro in the 15" or 17" size would seem to be more seriously considered here, as they possess a greater and more capable graphic card, screen size and resolution, which seems to be your primary desire.

Would the MacBook Air suffice? Possibly, but I still think the larger Pro models would be better.

Something else to consider. Some MacBook owners have been reporting some problems with the integrated video card/drivers that the MacBook Air & MacBook Pro 13" have with Adobe Photoshop. Whether similar sounding problems that I have had with PS have anything to do with this, is something I suspect. I have every confidence that these issues will be resolved. In the meantime, I would think that a new user would take this into consideration.

The choice depends on how you plan to use your Mac in conjunction with your photography. In my case, I shoot RAW images most of the time, then edit them. For this, I use a desktop Mac: a 27-inch iMac with a quad core i5 processor and 12 GB of internal RAM. For me, the quad core processor makes a significant difference in processing and adjustment of the images. And the 27 inch screen is spectacular. When I was considering the iMacs last year, the 21 inch model looked great, but the 27 inch model was just more impressive, particularly for photographs and editing.

I also have an 11 inch MacBook Air which I use when I travel. However, I do not use it for photo editing. It is mainly for email, internet, and work documents. For photography, it is used mainly to act as a conduit when I backup my CF card to a 500GB portable drive. The screen on the MBA is really too small to do any significant photo editing and it's internal memory is too small for backup purposes.

In sum, if you shoot RAW, get the most powerful processor you can afford. That would be an iMac or a MacBook Pro. On the other hand, if you shoot JPG, the Macbook Air might work, but keep in mind it's limited memory capacity and processing power. In any event, you'd probably be better off with an additional external drive.

You asked about photoediting on iOS. iOS is the mobile system used on the iPad and iPhone. The Macs like the MacBook Pro and MacBook Air run OSX Lion, not iOS. I assume you are going to edit your photos on your new Mac.

I'm using Apple's Aperture to do my photoediting on my iMac. I find it to be perfect for my needs. However, you can also use Adobe's Lightroom or Photoshop. I believe each of these programs has a trial download you can get for free, so it is worthwhile to try them all and determine which one works best for you.