What you actually have to do
You run the story. The app runs the bookkeeping β initiative, XP, levels, ammo, credits, reward payouts. If a number moved, a rule moved it, and you don't need to check its work.
Your controls live in the GM Console, the amber panel at the top of the sidebar. It's on every page, so you're never navigating away from a fight to award something.
Players get their own sidebar and their own Field Manual (the π button). You don't have to teach them the interface β point them at it and it explains their side.