How to use
FAQ: I don't understand. How does this app work?
This animation explains how WordUp works.
FAQ: Why is the level so easy? I want more difficult words.
By default, the system suggests a range based on your total known vocabulary assessment.
But you are not limited to that. In the Gap Map page you can see a line for every 1000 words, ranging from the easiest to the hardest.
You can pick any range that you'd like to focus on.