Honestly I cant find the exact one, but Reza Dorrani probably has this in his vids or you can go with something like this:

https://youtu.be/cC-skWfWOXQ

Tldr - in PowerApps you design the form and buttons, which set a value on a sharepoint list, after which you can set up the view as shown on the vid ive shared. I wish i could help more, but my PowerApps/Automate knowledge is limited.

PowerApps + PowerAutomate then? If you have such licenses and wanna go native MS then this works like a charm, even on mobile. Doesnt take long to prepare, i think it is even a PA example that MS has. Ill try to find it.

Edit: I know this is a selfhosted community but MS tools work well with MS tools :D

Afaik, MS Teams now has a native status thing, which shows you as either in Office or WfH. Would that suffice?

Edit: it doesn’t show up on my iOS app, so maybe it is on desktops only.