I am nearing completion of an app I have designed for iOS and tested on my iPhone 4. I bought a 2nd gen iPhone so I could test on both screen resolutions (320x480 and 640x960) before discovering AIR for iOS does not support very old iOS devices (I believe the rule is it must be iOS 4+).
My question is how is distribution handled if the app will not run on these older models? Wouldn't people with a 2nd gen iPhone still have access to an app that I publish via AIR for iOS and then be angry when it is not supported on their device? Has anyone run into this issue?
AIR 2.5+ requires iPhone 3GS+ to run. It's based on the CPU inside that
device and newer which includes a NEON SIMD coprocessor - a requirement
of newer AIR builds on all platforms (newer than PFI/AIR 2.0, which
shipped with Flash Pro CS5.0).
There should be a "resolution" drop down in the AIR for iOS Settings
dialog, if you updated your PFI in CS5.0 or upgraded to CS5.5. You can
select "High" to get iPhone retina display support. This will not enable
iPad 3 retina support though.
Edit: I didn't make it clear that the device requirements are set in your app, and enforced by the App Store - users on old devices will never see your AIR apps in their app store, and if they link into the App Store, they'll get an explaination of why they can't install the app (it'll be either the OpenGL ES 2.0 requirement, or the CPU requirement - it's similar to if you try to install an iPad only app on an iPhone). Android actually works the same way - old/cheap ARMv6 device users will not see your ARMv7 requiring app in their Google Play/Marketplace app.