Samsung Flow is something I recently discovered. It only recently become compatible with devices other than some of the Samsung Windows devices. You will need the Windows 10 Creators update. For you to be able to unlock your laptop with the fingerprint reader on your Samsung mobile device you would need the Samsung Flow app from the Windows Store
It was not available to install with region set to Trinidad and Tobago. You can change your region according to the instructions here. Also install the Samsung Flow app on your mobile. The Google Play Store lists the app as not compatible with my S8+ (SM-G955F). This was very strange to me. Maybe also a region thing but I realised I could install it from the Samsung app store
If your phone is already paired to your laptop then unpair it so that you can pair it from the app. Then follow the instructions to setup. You will need to create an Windows unlock PIN so that the app can unlock your laptop. More of what you can do with the Samsung Flow app here. Looks like there is some overlap with the SideSync app. Share your experience with us in the comments below. Let me know if it works with your devices.
Update (19 JULY 2017) – Trying to figure out how to get Samsung Flow to start at startup. Can’t see a setting for this. I put the app in the startup folder but the app starts after I login. Would be nice to have Samsung Flow fingerprint login after booting up laptop. Contacted the developers and this is what I was told – Samsung Flow does not support “auto start up” because Universal application is not allowed to register as a start up application. Only background task of Samsung Flow is started during booting sequence.