IPhone 4S due to the relatively aged hardware. In fact, some users often reported that performance on the 4S is very slow, similar to how iOS 7 ran on the iPhone 4, and suggesting that they should not upgrade due to battery draining issues and hanging up on calls. Meanwhile, Apple released iOS 8.1.1, which brought slight improvements to the phone and the iPad 2, but it still did not run as fast as newer models. On June 8, 2015, Apple announced at the WWDC that the iPhone 4S would support iOS 9. This makes it the first iPhone to support 5
IPhone instruction leaflet, but as with many newer iPod models the battery in the first generation iPhone has been soldered in. Therefore, a soldering iron is required to install the new battery. The iPhone 3G uses a different battery fitted with a connector that is easier to replace. The iPhone X features a different battery, with two battery cells, and the adhesive pull tabs are adhered to the sides instead of folded over the top, therefore making repairs a little more difficult than before. A patent filed by the corporation, published in late July 2013, revealed the development of a new