iPhone 4S users rejoice: Apple iOS 9 to be optimized for older devices - ExtremeTech
iOS 10 device compatibility list
iOS 10: Available Now
iOS 10 device compatibility list
How To Update iPhone To iOS 10.3 Beta 4 Using 3uTools? - 3uTools
Download iOS 10.3.4 on iPhone 5 Right Now or Lose App Store, iCloud
Downgrade iPhone 5 / iPad 4 From iOS 10 -10.3.3 to iOS 8.4.1 - 3uTools
question] Recently got my hands on an iPhone 4 running iOS 7.1.2. Should I jailbreak it? Btw it's a 32gb white, I also need to replace the battery. : r/LegacyJailbreak