Sums (free)

A simple but addictive number puzzle that trains your mental arithmetic.

How to play:

- Split the nine numbers into three sets of three numbers each, so that each set forms a 'sum-group'.
- For example, the numbers 11, 39 and 28 form a sum-group, because 11+28=39.
- Select a sum-group by clicking on its three numbers in any order. Undo by clicking again.
- Then select the next sum-group.
- There are ALWAYS at least three sum-groups in a puzzle !
- It may be necessary to undo an already selected sum-group to finish the puzzle completely.

Notes:

- The range of random numbers can be varied, using the '+' and '-' button.
- The app starts automatically after showing intro screen for a few seconds.
- The app has no ads, no in-app purchases and no risky permissions.
- The app is written with Python / Kivy and adapts to all screen sizes.