A simple list app

In the last few weeks I had to go to the house and measure humidity of a number of points. I used google keep with a checklist and just text an I thought:

Wouldn't it be nice to have an app which I could define a list of entries and then just be able to add values to the list, or even add/subtract a certain value?

App idea

I'd like to build a simple mobile ap where:

• the user can define a list of items
• for each list, the user can define:
  • an initial value (default 0)
  • an increment (default 1)
• the user can create an instance of that list
• the user can just enter values for each item
• the use can click on a +/- to increment/decrement the value for an item

It'd be nice :)