This marks a good time for 1.50, as the latest feature is one I've wanted to add for a while but didn't know how to do.

Now as a word reaches mastery, a star will fly down next to the button to show progress toward mastering that word. It doesn't appear each time, just at certain thresholds. 

Made some other minor adjustments as well as usual, but the stars displayin mastery progress is a big one, and I believe should significantly improve how the game feels. Let me know if the animation timing feels right and whether the stars are perhaps appearing too frequently or just right!