You can either make changes right to the database when the Cell is clicked, and use Conditions to highlight the Cell. Or you can use Custom States (recommended, but can be trickier to learn). Here is a link to a discussion about using Custom State lists
Then in the Conditions, you would put 'When Current Cell’s item is in Custom State lists, make background colour different".
Try playing around with the Custom State list and let us know if you have questions or post a link to the Editor (make the app public first) so we can go in and help
Geoff | Wolfer Tech
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