How to Make Learning as Addictive as Social Media | Luis Von Ahn | TED

• people with lots of money can afford better education
• people with little money can't afford good education and stay poor, this is especially true in poorer countries
• to help change this, the developers of Duolingo wanted to create an mobile phone app for learning foreign languages, because learning English can drastically increase your income potential
• you can learn as much as you want for free
• you can pay to turn off ads
• people from rich countries tend to pay to turn off the ads, thus funding the app for the poor

Any app on a mobile phone has to compete with social media apps. So the developers had to implement features to make learning addictive:

• streaks
• friend streaks
• quests
• friend quests
• reward chests
• notifications
• passive aggressive notifications, if you've been slacking too long
• competing in leagues: your first week, you're in bronze league in a group of 30. At the end of the week, the first 20 with the most XP go to silver league. In silver league, the first 15 get promoted and the last 5 get demoted. Then you progress to gold league, sapphire league, ...
• achievements