Here is the full list of all 9 3D Watermelon Game achievements.
Merge two bananas to get a watermelon!
Merge 2048 fruit. The minimum amount of cherries you need to match to get 2 watermelons
Drop 1728 fruit
Merge two peaches to get a banana!
Have some fruit leave the blender's gravitational pull.
In classic mode, achieve a combo of 10x
In Time Attack mode, survive for longer than 10 minutes in a single round.
In Auto Drop mode, survive for long enough to cap out the drop-rate of fruit.
Merge two watermelon to get a... Cherry?