iOS 13.3 improves battery life and performance on older iPhones
iOS 13 Latest Version, Updates, Problems, Fixes & New Features | Macworld
Battery jumping randomly to 1% on iOS 13.3? Anyone? : r/ios
iOS 13.3.1 battery life test follow up (Video) - Geeky Gadgets
Severe battery drain after updating my iPhone SE to iOS 13. 52 minutes of use, 50 in Pokémon GO completely drained my battery. iOS or Pokémon problem? : r/TheSilphRoad
Apple's iOS 13.3.1 Update Reportedly Drains iPhone Battery Fast
Is this normal battery life? iOS 13.3 94% battery health. Currently at 17% low power mode toggled on since 100% : r/iPhoneXR
Battery drain & iOS 13.3 | MacRumors Forums
New iOS 13 Features — The 200+ Best, Hidden & Most Exciting New Changes for iPhone « iOS & iPhone :: Gadget Hacks
Apple iOS 16 Release: Should You Upgrade?
iOS 13.3.1 Battery Test & More - iOS 13.3.1 Follow-Up - YouTube