A registered Apple developer tells Softpedia that iOS 7, in its current form, works extremely sluggish on iPhone 4 handsets.
Confirming my fears that Apple’s new software may not be a good match for the A4 chip, this developer said “[iOS 7] runs really slow on iPhone 4, the device heats up and everything takes longer than necessary to load.”
He went on to say that the new animation in iOS 7 (which zooms the UI in and out when you launch and close apps) is very fragmented and slow.
He also noted that some of the apps residing on his phone, including Skype, failed to run, but that’s normal since those apps haven’t been tested against iOS 7 to begin with.
Since the iOS 7 beta is what it is, we can take some comfort in knowing that Apple will do its best to iron out all the CPU/GPU hogs before the final version rolls out this fall.
However, as always, the oldest device models are the ones to take the biggest hit whenever a new generation of iOS software comes out.