You earn crystals as you complete lessons. You can buy more from the Shop tab

Duolingo
Learn Spanish, French and more
You earn crystals as you complete lessons. You can buy more from the Shop tab
More interactions from‏‏‎ ‎
Duolingo
During login, it asks for your age, name, email and password
You can tap the country flag on top to add more languages and switch between them
There are posts by other learners and mini "games" that help you test your skills
Duolingo Plus lets you download lessons offline and removes ad. You can start with a 7 day trial
First lesson complete. It shows your learning minutes and asks you to create a profile
Profile and settings
Asks you to select a daily goal and then notification permissions
Gamification badges and progress