Sorry haven't installed my Tab 3 in a Brodit yet so can't help with the pipe mount. I did a bunch of research but haven't bought a bike again yet so haven't had to mount it yet. Maybe contact Brodit to ask. They were helpful when I had a question. I think (not 100% sure) it uses the AMPS hole layout so you could also look at other pipe mount makers with AMPS holes. But Brodit should be able to confirm that.Research is time consuming but expect good results. Reckon you're right Hades about the Brodit way. Just got a s/h Samsung Active Tab 3 £150 & found Brodit active charge/lock mount & trying figure out which Brodit pipe mount for navigation rail but only 2 bolts so wondering if 4 bolt SW-Motech is better (if Brodit mount is visa 75).
Beauty about the Tab 3 is no battery option so should boot up when turn on ignition & power off with bike, so no need set the boot loader to power up if that was possible.
I had read a few cases where the active mount had occasional issues charging in the rain or dust, which is why I suggested the passive holder with a waterproof USB cable instead.
If you set DMD2 as the default Android launcher then it replaces the "home" screen when turned on.