Mahjong Spirit 2

It has 4 challenging levels.

The basic levels are for training your abilities and gathering items.

Mahjong Reversed - Look for the same pair of tiles but the other one must be inverted.

Mahjong Locks - Open the locks to free blocked tiles. Two locks of the same color must be opened in sequence. Otherwise, they will be re-locked.
Mahjong Infinity - New tiles will be added while you’re deleting the existing ones. Be quick!

Going back to previous levels blocks the ensuing levels and forces you to start from there.
Recommended for tablet screens.