[actarusweb]

Thanks for reply. 
I use MSP for sheets and for changing sounds to my keyboards.
With just 1 keyboard tablet consumption is perfect, 15 minutes 1% of battery. 
Now I started  using 2 keyboards. And even if I use a powered hub battery consumption is 10 minutes 1% .

I'm just a little afraid to use that stuff, I read about few problems,. so I was thinking about a tablet with a port for power supply. I start to think  that it will be a problematic search...

P.S: Lava stuff looks interesting. at the moment they are close for holidays, I'll take a look... next year. 

Many thanks 

Max