Yosumin! by Square Enix
Yosumin! is a cute little puzzle game that originated as this free flash game and it became so popular it was later upgraded and released on the Nintendo DS in Japan, and currently has a much fuller expanded version offered on Steam worldwide. This of this as an extended demo of the Steam version.

This is the original flash version, so it has no advertisements. It is about 10mb so it may take a few moments to load so please be patient.

You can play Yosumin! right here.