I get asked this question quite a bit so I put together a list of the best things you can do to free up space on your iPhone. There are many other ways but I feel these are the easiest ways to get back some of your storage. This will come in handy the next time you have to do a big update or if you keep getting the "Not Enough Storage" prompt.
1. Delete photos and videos
This may seem obvious but this is the easiest way to get your iPhone some extra space. Go through your camera roll and delete anything you don't need. After that, connect your iPhone to your computer using the USB cable that goes to your charger. If you're using a Mac, open iPhoto to import all those photos leftover onto your computer. You'll not only free up space but you'll have a bunch of extra room to take more photos and videos. Make sure when importing to choose "Remove Photos from iPhone" when you're done.
2. Delete old iMessage conversations
This is another easy way to free up space. Go through your iMessage conversations and delete the ones you don't need anymore. Every time someone sends you a picture or video, that takes up your precious storage on your iPhone. If there is a photo you would like to save, just tap and hold on the photo to save it your camera roll.
3. Delete unused apps
First thing you want to do is see what apps are taking up the most space. This is very simple to find out. Tap on settings>general>usage>manage storage.
They're listed by the amount of room they take up on your iPhone. Just go through the list and if you see an app on there that you don't use, delete it. Typically you'll find Photos, iMessage, Facebook, and Music at the top of this list. Also, if you have any games installed they will take up a good amount of space. Get rid of the ones you're not using anymore.
To delete an app, simply tap on the one you want to delete in the list and tap delete app. You can also do this from the home screen by tapping and holding on the app you want to delete. You'll see all the apps begin to wiggle, just hit the "x" and that will delete the app. Hit the home button to make the apps stop wiggling.
4. Delete and reinstall certain apps
Here's a secret that not many people know. Apps like Facebook, Instagram, Twitter and Spotify are continually saving things to your iPhone and never deleting them. They do this so the app does not have to download the same thing twice. Over time, this can take up a huge chunk of your space. All you have to do is delete them and download them again from the App Store. You won't lose any information. All you do is sign in again and you'll be able to use those app just like before but they'll be taking up much less space.
As you can see, just by deleting and reinstalling Spotify I was able to gain back 1.2 GB and I didn't lose a thing by doing it.
These are just few ways you can save some space on your iPhone. Let me know in the comments if you have any other tips.