iOS 8 brings the biggest functional increase to the iPhone and iPad since… forever. But it also brings the pain of 4GB of storage you need to free up before you can install it.

When you use Software Update to download and install iOS 8, not only do you need the space to store the file, you need the space to stage it while the update takes place. That might not be a problem on a 64GB or 128GB device. On an 8GB or 16GB device, however, it can be maddening. Luckily, there are several things you can do to make downloading and installing iOS 8 on your iPhone or iPad much, much easier.

1. Download and install iOS 8 using iTunes

Rather than use Software Update to wirelessly download and install iOS 8, you can go old-school and connect to your Mac or Windows PC via USB cable and update using iTunes. The advantage is that the download goes onto your computer, not onto your iPhone or iPad, so you don’t need anywhere nearly as much space. For many people, updating using iTunes is the quickest, fastest way to get iOS 8 on an otherwise storage-starved device.

Give it a try!
Make sure you have a recent iTunes backup.
Launch iTunes on your Mac or Windows PC
Plug your iPhone, iPad, or iPod touch in using your USB to Lightning or USB to 30-pin Dock cable.
Click on the device icon at the top left to go to the device tab.
Click on Check for Update in the Summary pane.
Click on Download and Update.
Agree to the Terms and Conditions.
Enter the Passcode on your iPhone or iPad, if prompted.

2. Clear out space on your iPhone or iPad

If you don’t have access to iTunes on a Mac or Windows PC, or simply don’t want to use it, you can also try deleting content from your iPhone or iPad until you have enough space to download and install iOS 8 directly.
Launch Settings from your Home screen.
Tap on General.
Tap on Usage.
Tap on Manage Storage.
Wait for all the usage stats to load.
Tap any app name to get a more detailed accounting of it storage.
Take a note of any app that’s using a large amount of storage. (Any app that has a number in GB (gigabytes) rather than MB (megabytes).

Videos is a prime offender, but it’s also easy to handle. Go to the Videos app and delete the movies and TV shows that you’ve downloaded. One or two movies, or three or four TV shows can easily give you back enough space to install iOS 8.

Likewise, Podcasts and magazines in Newsstand are easily re-downloaded, so they’re another great candidate for temporary eviction. As are really big games, like those with 3D worlds in them. If you’re not actively playing them, or don’t have a huge investment in levels or equipment you need to maintain, delete them for now. Those can save you up to a gigabyte or more each as well, especially HD video podcasts, giant PNG or PDF-rendered magazines, and epic games.

If you send and receive a lot of picture or video messages or MMS, that can chew up a lot of space. Delete any messages you don’t want to keep, and save any photos or videos to the Photos app that you do.

Then, deal with Photos. It can be a monster, especially if you’ve taken a ton of pictures, or any significant amount of 1080p video. Delete any you don’t care about, and either offload to your Mac or Windows PC, or upload to Dropbox, OneDrive, Google Photos, etc. any you do.

Delete what you care about least, then try the update again, and stop deleting as soon as it works. You don’t need an axe here, you need a scalpel.

3. It gets better

The good news is that once you install iOS 8, you’ll need even less space for future updates. Newer versions of iOS have cleaned up system storage and made updates smaller and more efficient. iOS 9 will be even better, requiring just 1.3 gigabytes to install, and even offloading and reloading apps automatically to make the process easier.

So, give all of the above a try, and if you have any trouble, let us know in the comments!

Recommend: You can also use Syncios to free backup old iPhone and transfer to new iPhone 6. You can also download and install apps into iPad/iPod/iPhone. There are Huge and growing collection of free gamesapps, wallpapers, ringtones for iOS devicesJust simply download and have a try.

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Reference: imore
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