I've thought about doing exactly that, but have decided to use a Windows Laptop (ultrabook format)
which has very modest power requirements, and it's fairly lightweight as well. If its internal battery
is fully charged before you go into the field with it, it draws a little less than 1 amp from my 12V
LiFePO4 battery. I used that setup for Field Day 2021, and it worked very well.
If you have your heart set on an android tablet, there is another piece of software to side load.
AndFLmsg, which is an android version of FLDigi. It's not a feature laden as the Windows version,
but I've used it on an android smart phone and it works pretty well. And as AA6YQ stated, you
really don't want to be logging QSOs using a touch screen. It will slow you down and limit your
QSO rate while operating POTA. Do yourself a favor and invest a few bucks in a bluetooth
keyboard to go along with it.
It is interesting to note, that long time portable digital QRP guy Julian, OH8STN has recently changed
from using a raspberry pi with an android tablet and bluetooth keyboard to a Microsoft Surface 2 tablet.
He found that there was some software he really wanted to be able to use that was just too kludgey to
run on a raspberry pi, but worked just fine on Windows. He also really likes how that change has
simplified his field setup.
73 de N8AUC
Eric