Step 4 of 19: Find out which apps are taking up most space
A handy way of finding and deleting the apps that are taking up the most space is to go to Settings > General > Storage & iCloud Usage, then tap Manage Storage in the first section (STORAGE, rather than ICLOUD). Wait for the apps to appear under storage (it can take a minute or so for them to appear).
Your apps will be presented in order of how much space they take up. Anything near the top of the list that you don't use regularly should be a high priority for deletion.
Scroll through the list and be brutal. You will find the biggest space wasters at the top - probably your Photos and Music apps (the figure includes media that the app stores/organises as well as the app itself), but your Messages app may be there too if you receive a lot of text messages with images in them.
If an app you rarely use is taking up 300MB of space then delete it - you can always download it again for free if you want to. Once you have bought something it's tied to your Apple ID so Apple knows you own it.
Step 5 of 19: Delete Documents & Data you don't need from apps
To look deeper into the storage space being taken up by apps, look again at Settings > General > Storage & iCloud Usage > Manage Storage and click on the arrow beside one of the apps listed there. This way you can see how much data is used by the app itself, and how much additional space is being used by documents & data.
For example, our Pages app has 4.9MB of data; with a little tidying up we could ensure that those documents saved on the iPhone were moved to the Cloud where we have a lot more space.
Are there any apps there that have data associated with them that you no longer need on your iPhone? For example, the iPlayer app is 46MB, but we have 512MB of data associated with it, which suggests we have downloaded some programs at some point that are still lurking inside the app.
Go to the iPlayer app and delete them.
Step 6 of 19: Turn off Photo Stream
If you have Photo Stream turned on you will see photos you have taken on your iPhone or iPad, and those you have uploaded to your Mac from your camera. These images aren't full res, but are still likely to take up a lot of space on your iPhone. If you could really do with that extra space then turn off Photo Stream.
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