Thank you - glad you liked it and thanks for sharing your impressions and feedback; helps me understand what the users like.

> Dunno about the trigrams though, mostly it's on the "token group" level for me - either the upcoming lookahead feels familiar or it doesn't, and I don't much get bothered by the specific letters as much as "oh I don't have muscle memory on that word, and it's sadly nestled between two easy words, so it's going to be a patchy bit of alternating speed".

Could you elaborate a bit on this part - not sure I fully follow.

The trigrams/bigrams is mostly to help the user discover if there are some patterns that really slow them down or have a lot of mistakes. This is something I wanted that I didn’t see in any other apps.

This also what we use under the hood for SmartPractice weak point identification. We look at what the most relevant character sequences (for example the ta sequence is way more common than za) are and what the user struggles with the most. This is just one of the weak points we use in the user weakness profile.