I have had the same issue with both my Jawbone UP24 and Fitbit tracker and all issues started after the latest software update from Samsung. We have tried the following steps as suggested with no resolution:
Clear app cache/data
Uninstall / reinstall the Jawbone and Fit-bit Connect App
Turn Bluetooth on / off
Turn airplane mode on / off
Unpair the device - phone states it 'cannot communicate with either device and will not pair .
Has anyone been provided with a solution to this issue?