Beginners Question ... Logging & Exporting data

I think the About page on the Bangle shows free space, but honestly it's not such a big deal. Maybe each line of data uses 40 bytes, but the Bangle has 8 megabytes - so recording every 10 seconds that's over 23 days of recording 24 hours a day.

Also, is there a way to connect the JS2 to multiple bluetooth devices at the same time?

Yes - well, you can connect to the Bangle, and the Bangle can connect to 2 other devices (eg heart rate monitor) all at the same time.

If you want to connect to the IDE and to Gadgetbridge then that feature has just been added: https://forum.espruino.com/conversations/386264/#comment16973189

saving the recorder date to a windows or linux box directly (opposed to save on Android initially) would save me a step

Perhaps the easiest is to fork the app loader (https://github.com/espruino/BangleApps) and enable GitHub pages, then change the settings in Gadgetbridge so it loads your version.

Your version of the App Loader could then read all your data and sync it with an HTTP POST to whatever server you wanted whenever you clicked the App Loader icon in Gadgetbridge.

10s was the duration it is logging data for, not the interval at which it records it seems.

it records one data point every 10 seconds.

At least I tried activating record twice and both time it turned off again

So you just tapped the box next to the text RECORD once and you're saying it automatically turned itself off after 10 seconds? I just tried it here and that's not what happens at all.

You said I could define the interval, but there is no option for it

It's called Time Period

nor for the temperature mentioned in the manual

I'll update the docs to make this clearer - for Core you need to install the coretemp app. OR... Turn on Log Baro and it'll use the built-in barometer to record Temperature, Pressure and Altitude