I know this is a very specific question, but maybe this is something easier that what I think, so it is worth asking here:
How can I connect to a watch via bluetooth, and get the data it holds inside? The watch is able to deliver this information, but as of now there is only an iPhone app for this task.
I have a watch (NewBalance LifeTRNr Sync) that measures your hours of sleep, how many calories, steps and kilometres you have made in the current day, and keeps a record of them for the last 7 days.
This device can connect via bluetooth to another device and can transmit this information (at this moment there is only an already implemented app for iPhones, but I only have an android smartphone).
At least, my laptop can see the watch, because
bt-device -l gives this output (I don't show its mac address here so that I don't make it public):
$ bt-device -l Added devices: Life TRNr Sync (**:**:**:**:**:**)
And when I try to pair the watch with the laptop (Debian jessie 8.0, with Gnome Shell), the watch shows the icon that is meant to be displayed when the connection with the app is being performed, so I can think the watch receives the pairing signal from the laptop, but obviously nothing more happens.
What can be done to talk to the watch, in whatever language there is, and try to get the data out of it?