There are only a few options to pick from when you download a gedcom.
Go to the help menu in the upper right corner of the screen. Go to gedcom, and read through the section. You will get to the part about downloading a gedcom from WikiTree.
You choose the starting person, choose ancestors or descendants, and the number of generations (which is limited to 15). There are some options about file size and privacy to pick from as well.
The WikiTree gedcom includes reference numbers in the data fields. They all have the same label, but one is related to the privacy level, the others are a code for the profile manager(s). If your software imports these, it should be easy to pick the one that identifies you (look at the people that only have you as the profile manager) and then export “your people” based on that reference number.
On the tablet perspective ...
I have tried four different tablet-based genealogy systems, quite frankly, I find them less than optimal. Desktop software, in my view, is the better option.
Web-based systems are ok, but they are easier to use on a desktop machine or a laptop.