v6.3: Support sentence translation in native languages

v6.2: Improve quiz: Smarter quiz option

v6.1: Hot-fix: Can not play audio issue on Android 10.

v6.0:

- Allow listening & practice selected groups.

- New stunning theme colors

- Learning targets: New feature to help the user keep track of your progress

- Many bugs fixed: Ex. The issue in 'Play all' feature