Hello everyone,
I’m new in this community and recently started working with OpenHAB. My question, is anyone already working on a binding connecting Fitbit or other smartwatches with OpenHAB?
EDIT: If not are there any suggestions how to get started?
Thank you 
Some have been successful with BTLE detection, but this does require you have a bluetooth hardware of some kind with OH configured to leverage it.
What are you trying to accomplish with detecting the fitbit?
My goal is to display most of the relevant datas from my Fitbit (e.g. pulse) in my Smart Home. My bluetooth hardware could be my laptop, right?
If you are after your fitbit data, perhaps pulling it from your account via the HTTP binding is the way to go; I’m not familiar with their API, but it would have no need for BTLE at that point just data pulling on your fitbit account.
https://dev.fitbit.com/build/reference/web-api/ should get you started. If you use OAuth2 using just OH Rules and myopenhab.org you can prototype it using just OH Rules. But because it uses OAuth2 you will want to eventually turn this into a binding.
There has been a lot of work recently to improve the Developer Guide so that should be your starting place. But be aware there are a number of changes occurring with the build system which might throw some problems you way but there are a bunch of good posts in the Developer section of the forum to help you get past them.
Thank you for your helpful answers! I will work on it and keep you updated
Is there maybe a similar existing binding, which uses OAuth2 to access data from APIs?
I’m sure there is. OAuth2 is a common way for services to authenticate with each other.
Just curious, have you made any progress on this? I too would like to pull data for display purposes within my OH2 setup/