The app includes several in-app purchases that allow you to upgrade to get bonus features, such as custom backgrounds, icons, and fonts.
Other Keep Calm apps limit you to you five lines of text, however Keep Calm will allow you to type unlimited lines of text and customise which lines appear smaller.
Furthermore, Keep Calm Creator is the only app that will save all your posters in the app, allowing you to edit or share them later. Posters can be shared as high quality PNGs for social media, or PDFs for printing.
You can find more information about the images used in Keep Calm here.