Hey LarsNyborgPedersen,
Answering some of your questions:
Would it be best to put it in a .CSV
It seems like CSV is the most universal format now (at least for such kind of that), so I’ll bet on it.
Would there be any benefits to making this a local desktop app instead of a webapp?
Of course. If you’ll decide one day to switch over from Macs to Windows (or otherwise) - web application has you covered.
Are there more automated ways to get data from my 5-8 different trackers to my webapp? Not all of them have public API’s.
That’s true - some of them are not public, some of them are public but you have to pay for the REST API data access (and I think it’s fair taking into account that storage and processing can cost plenty). I’d stick to one platform that allows you to backup/export data to CSV anytime you want.
Hope that helps