iOS 27 bugs: iPhone users report lag, battery drain, overheating and random restarts

Apple's latest iPhone software update, iOS 27, is facing complaints from users reporting a range of performance and battery-related problems. Reports on X suggest the issues affect both newer iPhones and older models.

Among the problems being reported are sluggish or unresponsive screens, choppy animations, increased battery consumption, overheating and unexpected restarts.

The complaints come shortly after Apple rolled out iOS 27 earlier this month alongside its latest devices.

iPhone users report slow and unresponsive screens

Some users say their iPhones have become less responsive after installing iOS 27.

A user reported that changing Home Screen widgets could cause the entire user interface to crash, with a restart reportedly needed to restore normal operation.

Other users have described stuttering animations and frame-rate drops while using apps including Reddit, WhatsApp and Wallet. One iPhone 17 Pro Max owner said the slowdown was particularly noticeable when swiping or moving between screens.

The reports suggest the complaints are not limited to a particular iPhone generation, with users of both newer and older models describing performance problems.

Battery performance is another concern raised following the iOS 27 update.

One iPhone 15 Pro Max owner said their device was consuming more battery after upgrading to iOS 27. 

Some users have also reported overheating after installing the software. One iPhone Air owner linked the increased heat to the update while discussing the battery drain they had experienced.

It remains unclear from the user reports whether all of these battery-related issues have the same cause.

Last week, iPhone owners reported that their new devices were restarting unexpectedly. According to the reports, the restarts were particularly noticed while using Face ID or during phone calls.

There has also been uncertainty among users about whether those restarts are related to hardware or software.

Apple is expected to address the reported problems in a future software update. iOS 27.1 is expected to arrive alongside the iPhone Duo on October 23.