About 50 MB the first time. After that everything runs on the phone: no internet needed during the trick.
Spread the deck face up. Tap below, then move the phone slowly along the spread until all 52 cards are green.
Spread the deck face up, left to right, every corner showing. Fill the frame with the spread.
In order, left to right. Tap a card to remove it if it was misread.
Spectator cuts and pockets the top card. Show the bottom card to the back camera, about 20–30 cm above the phone.