I don't get enough memory for iOS 8 update, how to free up space on my iPhone? Running out of storage space on your iOS devices is annoying, and if you encounter with the following situations, you should be aware. They are signs that your iPhone, iPad or iPod is short of space.
The most common culprits when it comes to storage issues are videos, photos, messages and apps. You can just delete them if they are no longer useful. (Before you delete them, it's safer to backup them to your computer.)
However, even though you have deleted them, the caches cookies, etc. might remain on your device. To completely free up space on iPhone, iPad and iPod, you need clear caches, cookies, offline files and other files. Here's a free way to get rid of them.
After the cleaning, your iPhone, iPad and iPod should have enough space so that apps will run smoothly without crash. It's highly recommended that you use iCareFone(Free iPhone Care) to free up space on iOS devices regularly.