While Apple attempted to offer updates to the core system for much older devices, some other smartphone manufacturers often don't release updates even the base

While Apple attempted to offer updates to the core system for much older devices, some other smartphone manufacturers often don't release updates even the base system from the software company have updated that already. See Android phone's 2.2 froyo availability as an example. What Apple is wrong is to force 3G users to upgrade, given that quite a lot of new features are only available to 3GS and beyond. Also it is actually possible to downgrade from iOS 4 for 3G models, but it seems to be impossible to restore data to iOS 3.X from the backups of iOS 4.X.