Since iPhones don’t have expandable storage, you’re stuck with the amount of storage that the phone comes with.
If your phone is getting crowded, you might need to clear up space. While deleting downloaded music and transferring pictures are two solutions that come to mind immediately, I’ve got another option that can help.
First, take a look at your Message settings. Your iPhone will keep your messages forever unless you tell it otherwise. Now, you may want or need to keep all of your messages. But, if you’re willing to part with them, you can clear up a lot of space, especially if you text a lot. Go to Settings and then select Messages.
Scroll down to Message History and tap Keep Messages.
You can choose between 30 days, 1 year, or forever.
Depending on how often you send messages, this has the potential to free up quite a lot of space.