Here is the full list of all 17 Ichi achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Complete 10 levels.
Complete 5 levels.
Create & Publish 1 level.
Create & Publish 5 levels.
Create & Publish 10 levels.
Let 100 people play your level(s).
Complete 25 levels.
Complete 50 levels.
Complete 75 levels.
Let 10 people play your level(s).
Complete 100 levels.
Tap 100 times.
Tap 500 times.
Tap 1000 times.
Get a score of 100 points.
Get a score of 500 points.
Get a score of 1000 points.