Customers who use search to find applications on the App Store will now see results based on your designated keywords. The use of keywords replaces search results based on terms found in your marketing description. This new method provides customers with more targeted results and, with the proper use of keywords, greater discoverability of your application.

You can facilitate a better search experience for customers and create better discoverability of your application by assigning keywords that are specific to your application’s features, functionality, or user experience. Carefully choosing your keywords is also important because they’ll be reviewed during the app review process. If you misuse keywords, your application may be rejected and you will be asked to edit your keywords before you can resubmit your application for review. In addition, once you’ve assigned your keywords you can only change them when submitting an application update or if your application is in the Rejected or Developer Rejected state.

You can find more details about assigning keywords by reading App Store Quick Reference: Assigning Keywords For Your App.