As iOS progressed, update after update, app developers have rightly kept up, and minimum system requirements have been gradually obsoleting older generations of iOS devices. The process has been a bit painful for those users who haven’t been upgrading to a new iPhone every time a new model was introduced. I myself, after purchasing an iPhone 3G in 2008, have held on to that model until the iPhone 4 came out, therefore skipping the 3GS entirely. 

In the past, an annoying phenomenon that happened to me more than once was the ‘update with no return’: I would update an iOS app from iTunes, iTunes would update the app on the iPhone 3G during sync, and then I would find out that the update required at least iOS 4.3 to work (the iPhone 3G didn’t go past iOS 4.2.1). Result: I was left with an app no longer working, without the possibility to go back because the App Store kept only the most updated version of its apps. The only option was to stop updating (especially in iTunes) or keep around the older .ipa files to sync back to the iPhone in case of accidental, fatal updates.

But with the recent change Apple introduced in the App Store, which allows older app versions to be downloaded , things have really, surprisingly improved. At first, I just thought that this change worked only for relatively recent app and iOS versions (say, if you needed an iOS 5.x‑compatible version of an app to use on your original iPad), but it turns out this works even for much older versions — if, of course, an app has been around long enough to exist under iOS 3 and 4. 

For instance, earlier today I discovered I still can tweet from the old iPhone 3G. In this particular case, what actually surprised me was that, evidently, Twitter has made even old versions of its official client compatible with their new APIs.

After making this discovery, I tried looking for other useful apps I’ve discovered post-iOS 5, and I was able to download a few of them and see them work under iOS 4.2.1 on my iPhone 3G. (I was particularly glad to be able to use Scotty, which is a great app for wirelessly transferring photos and videos from an iOS device to your Mac or to another iOS device.)

I really appreciate this move by Apple, because thanks to this newfound backward compatibility, iOS devices as old as the iPhone 3G or 2nd-generation iPod touch can extend their usefulness and capabilities, and they feel a little less obsolete than before.