Here is the full list of all 21 Little Dog achievements.
Click on "Menu"
Reach level 12
Die 30 times from bat
Reach level 11
Die 30 times from cliffs
Reach level 10
Reach level 9
Reach level 8
Collect 40 bones
Reach level 7
Reach level 6
To be at level 5 for more than three minutes
Reach level 5
Reach level 4
Reach level 3
Die 25 times from plants
Jump 100 times
Reach level 2
Click on "Exit"
Click on "Play"
First level started