Here is the full list of all 24 Smile For Me achievements. It takes around 5-6 hours to unlock all of the achievements on Windows.
Forgive and forget.
Leave unfinished business at the Habitat
Escape the Habitat
Some crimes can’t be forgiven.
Satisfy every habitician
Grip a Y’owl for Borbra
Find every diary page
Clean Kamal's teeth
The secret’s out...
Find the Duck’s true owner
Dispose of the Duck
No thank you ma’am
Accept a smooch
Satisfy 15 habiticians
You really went and did it, huh?
Unlock the Terrace
Help a friend in need
Find an alternative route
Discover a hidden sweetheart
Get a very high score at Whack-a-Molar
Unlock the Lounge
Unlock the Carnival
Hit Ronbo with a golf ball
Satisfy a Habitician