So I understand that you need to pay the license fee to utilize the API to take fitness data from the garmin website. What im wondering is, if I were to build an app using the SDK on a Garmin Device, could I theoretically send the fitness data to another app/source? I.e. sending GPX tracks to my own backend and doing what I wanted with them? Could I export older GPX tracks as well?
There are two things you're referencing: the Connect API and the Connect IQ SDK. These two things, though similarly named, are different things.
The first requires a license fee, like you mentioned, and allows you to work with fitness data on the Garmin Connect web site. The second is a free SDK that can be used to write apps that run on compatible Garmin devices. I hope I'm not coming across as patronizing--I just want to make sure it's clear what these two things are. :)
Using the 2.1.x Connect IQ SDK you can write an app that will record custom (or standard) fitness data to FIT files, which can be used by any site or external application that knows how to read the fit format. We're adding the ability to use the custom data on the Garmin Connect web site, which will not require a Connect API license.
Right now, we don't have the ability to record anything but FIT files, but we are looking into providing ways to work with navigation data (e.g. routes, waypoints, tracks, etc.), which may include GPX files.
