I’ve been using Skritter for about 3 months and it’s by far the best app for learning characters I’ve used. Some of the metrics on the stats page are a little bit weird though. I’ve used the app pretty much every day since I started using it but my longest streak has never gone over 31.
My guess is that this has to do with all the data on the “this month” card using data that was pulled over a rolling 31 day period. It might make more sense to move “longest streak” to the All Time card.