With Windows (and Phone) 8.1 there were two different device capabilities which needed to be set to use either RfComm or Bluetooth LE from your app. You had to specify a target device (or All) and target service name(s). With Windows 10 there is a simpler option. You still have to edit the appxmanifest code as it is not visible in the manifest designer but you can set simply:-

<Capabilities> ... <DeviceCapability Name="bluetooth" /> </Capabilities>

This gives you access to all Bluetooth functionality from your app. This is a much simpler approach and less prone to errors. Most of the documentation doesn’t mention this new value except for this page:-

What’s different in Windows 10 Insider Preview

“new valid values are “bluetooth”, “wiFiControl”, “radios”, and “optical”.”

These are not mentioned on the “App capability declarations” page so it’s not clear which specific APIs the other intriguing values relate to…