Duolingo: best for a daily free habit across 40+ languages
Duolingo has the largest install base on this list. The store text describes short lessons covering speaking, reading, listening and writing, with chess, math and music courses added alongside the language ones.
Progress is tracked with rewards and achievements, which the developer ties to building a daily routine. The app is free to download, but it shows ads and sells in-app purchases.
Pros
- 4.7 rating and over 500 million installs on Google Play
- Covers 40+ languages plus chess, math and music
Cons
- Shows ads
- Includes in-app purchases