I'm developing a 3D running simulator and I'd like to include displacement and altimetry data from my activities. How can I do this? I have Garmin 235
You can export the activities in multitude of file formats, in Garmin Connect Web, and use that data for your simulator. Or you can download the original FIT files directly from the watch using the USB cable. Or you can use the JSON data used for feeding the GC Web pages. You can also write a Connect IQ application feeding the needed data live to a server.