A lot or a little?
Parents need to know that Puku: Learn New Words is an educational app from Merriam-Webster designed to help kids 8-12 learn new words. The app supports multiple profiles allowing each player to track their own progress. While each profile is assigned an age, the words don't seem to change at all based on the age of the user, so don't rely on the app to choose age-appropriate words. The app supports user-created lists but lacks a tutorial/guidance on doing so. Read the developer's privacy policy for details on how your (or your kids') information is collected, used, and shared and any choices you may have in the matter, and note that privacy policies and terms of service frequently change.