The free version works as intended, however avoid purchasing the in-app content upgrade. The app locked me out with a looping pop-up window asking for Apple ID and password immediately after payment. I was unable to reach the developers, and my efforts to report the issue to Apple through “Report a Problem” were ignored. I was unable to receive a refund, and cannot use even the free version of the app anymore. If you enjoy the free version, don’t pay for more, as you will only receive less.