Here is the full list of all 11 Zipple World 2: The Sweet Chaos achievements.
You saved 500 frogs
You killed 500 enemies
You unlocked the third world
You saved 100 frogs
You unlocked the rock world
You killed 100 enemies
You saved 50 frogs
You killed 50 enemies
You saved 10 frogs
You killed 10 enemies
You have passed the level 1