Andaman7 was developed to serve the vast majority of mobile users. That is why we developed our app on the 2 main operating systems: iOS (iPhones, iPad, iPod Touch and Macs with an Apple Silicon - see here) and Android (smartphones and tablets).
A7 supports a number of OS versions in order to cover 95% of the installed base at least. This means 3 versions on iOS and about ten versions on Android
Without any judgment on the product or its use, the number of people using Windows Mobile OS is too small in comparison to iOS and Android. The work load to develop and support a solution for Window Mobile would be too time consuming for a small company like us.