I use SkySafari 5 Pro together with my telescopes Meade LX90 and
Celestron Nexstar.
To control I use FireFly BT, because SkyBT is not sold in Germany.
The connection between Telescope and SkySafari on my Galaxy Tab S2
tablet sometimes takes a minute. Sometimes it does not work.
I also connected my notebook to my telescopes via Bluetooth. Both
programs (Skysafari and Carts du Ciel) connect without problems in a few
seconds! (= cable O.K.)
Maybe you have useful hints.