Here is the full list of all 38 Castaway Paradise Complete Edition achievements.
Grow every type of flower
Grow every type of fruit
Grow every type of crop
Donate all shells
Donated every collectable
Make a profit of 5000 gems on the Stock Market
Make a profit of 500 gems on the Stock Market
Rebuild Angus' Trailer
Remove 25 cobwebs
Rebuild the Lighthouse
Rebuild Amelia's Planehouse
Donate all bugs
Rebuild Victoria's Mansion
Donate all fish
Donate 15 shells
Live the luxury life of a VIP
Unlock the second room in your house
Used every piece of equipment
Harvest 50 crops
Donate 15 fish
Make a profit of 2000 gems at the Bank
Unlocked a gate
Remove 50 weeds
Donate 15 bugs
Collect 25 pieces of garbage
Completed 100 quests
Donate a collectable
Rebuild Harold's Museum
Rebuild Francis' Pirateshack
Rebuild Gustave's Bakery
Read 50 chit chats
Rebuild a bridge
Changed every piece of outfit
Wore an outfit of the opposite gender
Remove 25 stones
Completed 25 quests
Get your first collectable
Completed the tutorial