If you’ve been using your iPhone for a long time, you’ll have built up quite an archive of text messages. 
This can take up a lot of unnecessary space (do you really need those texts and pictures from 
two years ago?). iOS 8 now allows you to automatically delete these old messages after 

either 

30 days or one year, potentially freeing up gigabytes of storage. Tap Settings > Messages 

and scroll down to Message History before selecting how long you’d like to keep your old 

messages.