Testing iPhone Software on Different Versions Of OS

Question

Before submitting my app I want to test it on devices with the full range of iPhone OS available. So, I have 2 questions that I am struggling with and would greatly appreciate any help or advice.

What versions of the OS are in use?
I know that the App Store will only accept apps for 2.2.1 and 3 but all the features I'm using have been available since 2.0. Is it safe to assume that everyone is running at least 2.2.1?

Where can I find the other OS disk images, so that I can do the test?
The iPhone Development Guide (p43) says search the developer website but I can't find them.
Searching the internet just seems to throw up jailbreak sites.
I can see some dmg files that were installed with the SDK at:
Macintosh HD/Developer/Platforms/iPhoneOS.platform/DeviceSupport/x.x but XCode Organizer ignores them.

Any help or advice would be greatly appreciated. Many thanks in advance.

Answer 1

If you just need to test it on the simulator (which is a good approximation of the actual iPhone OS as far as API's are concerned) you can change the OS version by going to Hardware > Versions and selecting your version on the iPhone Simulator app. For me, I see 2.0, 2.1, 2.2, 2.2.1 and 3.0.

Edit: Here's a site that has older versions of the iPhone firmware: http://www.felixbruns.de/iPod/firmware/ Theoretically you can just "restore" to these older firmware through iTunes, although I haven't tried doing it myself.

Answer 2

What versions of the OS are in use?

Unfortunately this information isn't readily available. I'd love to know. It's clear that virtually all iPhone owners will have moved to 3.0, since it's a free download and there's no good reason not to. For iPod touch users it's not quite as clear, but my guess is that a good chunk of them have not upgraded. I would speculate that there is a strong correlation between the people who have upgraded at the kind of people who pay for applications, but speculation isn't necessarily a very good business case!

Where can I find the other OS disk images, so that I can do the test?

If you want to be all official and above board, you actually can't downgrade an iPhone or iPod touch to an earlier OS release. There are ways of doing it but I can't tell you what works and what doesn't as I've never tried.

The way I do it is test on my handset which usually has the last released version or a late beta. I then use the Simulator and my beta testers to check out how it works on older versions.