Your app has a button on its front page. No one ever presses that button. With good telemetry, you will know this and remove the button. The only thing you need to know is how many times each user opens the app and how many times they tapped that button. Crash reports can include the causes of errors. Without this data the app might have that unused button there forever and crash everytime anyone taps the donate button and you wouldnt know why you arent getting any dontaions.

Telemetry is usually collected on non metered networks. Usually it is opt-out by default, set by the user in the apps settings. Personally, I’d inform the user of this and let them decice on first startup.

Check the CPU, every NUC has a different one. An 11th gen i3 (i3-1115G4) will generally offer better performance than a N100 but a N100 may offer slightly better power efficiency since it was designed for it and is newer. Also when keeping in mind power draw and thermal efficiency, newer CPUs will usually do better. I personally would stear clear of older machines for that reason.

NUC is good for transcoding if you really need it. NUC11 i3 i think has 30w tdp and draws sub 10w at idle and does transcoding fine. Check specific HW codec support for your needs but stick to Intel because they will generally be the best in this space.

Also can confirm Jellyfin doesnt run well on a rpi4. No problem on a NUC.