All machines on the Island Farm can be upgraded with Mastery points. Mastery points are indicated by blue stars on each machine. The more stars you obtain, the more items you unlock. Tapping any machine on the Island farm will show a pop-up screen with the amount of blue stars you currently have (see image below).

 

Everytime you create a product with a particular machine on the Island Farm you will get Mastery points. These Mastery points only count for the same type of machine. For example, if you need to produce Wool Cloth with the Loom, the Mastery points you get will only count for all the Looms you have on the Island Farm.

 

If you want to know how many points you need to unlock the next Mastery level, tap the question button next to the blue stars (see image below).

 

 

Then you will see how many points you need for the next star as shown below.