Here is the full list of all 26 A Walk With My Dog achievements.
You finished the walk
Picked some tasty mushrooms
Took the plastic trash back home
You solved all the puzzles
You "fought" the snowman
You heard the bell at the church
Find the buried treasure
You lost the dog but then you found it again
Have you ever questioned the nature of your reality?
Hit all the lillypads
Collect three special balls
Made the dog quite happy
You let the dog enjoy the squeaky toy
Why did you touch it?
You found some photos
Keeps the doctor away
Find all photos
Walk 10,000 steps
It looks like my dog
You put the pieces back together
Can I call him Pepe?
Play tug for at least 20 seconds
You caught three types of animals
You scared a big bird flock 4 times
You got a good score on the game console
You took him back home to the garden