IOS8. 1 firmware takes up a lot of memory, which prevents iOS7 users from upgrading. Apple released iOS8. 1 this morning, which is the first major update of iOS8, bringing some new functions (such as Apple Pay function of iPhone6 and iPhone6 Plus) and fixing some problems. However, Apple doesn't seem to have fixed this major problem of iOS8: it prevented many iOS7 users from upgrading.

Upgrading iOS 8. 1 for IOS 7.x or iOS 8.0.x devices has some requirements for body storage, and the actual downloads seem to be few: 70MB for iPhone4s running iOS8.0.2, 126MB for iPhone6 running iOS8.0.2, and 140MB for iPad Air running iOS 8.

However, if you want to upgrade iOS8. 1 directly from iOS7.x, you need more storage space. For example, the iOS8. 1 OTA update of the iPhone4S running iOS7. 1.2 requires a huge 4.7GB (pictured).

The data released by Apple to developers shows that the recent usage growth of iOS8 has almost stopped, and the usage rate is much lower than the previous iOS7 update. Although there are many reasons why users choose to continue using iOS7.x instead of upgrading iOS8, many people suspect that the large storage space required for Apple's iOS8 upgrade is the real reason for users to make this decision. It is worth mentioning that users can connect devices to Mac or Pro and upgrade them through iTunes, thus bypassing the requirement of large storage space.