(I wrote about it a bit here: https://www.typequicker.com/blog/learn-touch-typing)
It has everything you might need to improve.
Topics mode: type text snippets from books, wikipedia, etc on various topics of your choice
Drills: Focus on specific character patterns
Custom: practice anything you want
SmartPractice: AI-generated natural text based on your weak points. The more you type, the more the system learns about your typing habits and uses AI to generate natural text.
We also have type racing and a daily leaderboard (same text for everyone, have a chance to get on the Daily leaderboard.
I built this app and used it myself; over time went form 40wpm -> ~120wmp.
Any feedback is appreciated.
Hope this app helps you as it has helped me!