Ink Calendar is available on Windows 10 Mobile. I made this decision because the core functionality of the app works reasonably well on a mobile device with a decent sized screen. Also I want to build a backend for to sync the ink across devices.
While testing new features on my Windows 10 Mobile device I discovered that there were some strange behaviors. When adding the share, save, and print capabilities they would immediately crash the app on mobile. No warning, no exception thrown, no error message while debugging.
When adding the ability to cut, copy, and paste ink the code was fairly simple. I followed the sample app supplied by Microsoft and it was easy to implement. When testing this ability on mobile I got strange errors and the functionality was not there. The ink content presenter could never paste.
These are fairly minor issues and the core functionally of the app is still there, but the errors are odd. Errors like this make it more clear to me that while Microsoft likes to tout how Windows 10 and Windows 10 Mobile can both run UWP apps… that just is not true. Windows 10 Mobile is so different from Windows 10 that it needs not just UI tweaks to make apps work.
Hopefully any mobile device from Microsoft in the future will come from Windows 10 because that would simplify development and make Ink Calendar way better on that mobile device.