Regularly remove junk files that  clutter your storage space or slow down the phone's performance.  
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 From the Home screen, tap  , and then find and tap Boost+. , and then find and tap Boost+.
- Tap Clear junk.The Boost+ app will show you how much storage space is being used up by different junk files, such as cache files, ad files, temporary files, and app installers. 
- Select or clear the junk file types you want to delete.You can tap  next to a category to view the files under it. next to a category to view the files under it.
 
- Tap  to clear junk files. to clear junk files.
Note: In the Boost+ app settings, you can also choose to get notified when your junk files exceed a set limit or when an app is unused over a period of time.