How do cards stay private on one screen?

Between turns, a handover screen asks you to pass the phone to the next player. Their hand appears only after they confirm that the opponent has looked away.

Which Uno rules does this mode use?

+2s and +4s stack separately, cards with the same rank can be chained, and forgetting to call Uno leaves you open to a two-card penalty.

Two-player Uno on one phone

Two-player Uno

A duel on this device: take turns, and hand the device over between turns.

Rules in this version

A skip or reverse skips your opponent: it's your turn again. It doesn't stack — playing three doesn't give you three extra turns.
+2s stack between players. Whoever can't answer draws the whole pile, then plays: their turn goes on.
+2s and +4s each stack on their own and never mix: no +4 on a running +2 chain, and no +2 on a +4 chain.
You may play several cards of the same rank in one turn (red 9, yellow 9, blue 9), but only one wild per turn.
Finishing on a wild or a +4 costs 2 cards: you can't win on a black card.
With no playable card, you draw until you get one, then you play it — including right after taking a stacked pile.
At one card, call « Uno ». Forget, and your opponent can call you out for a 2-card penalty.

This Uno duel fits on one phone without exposing the other hand. Each player reveals their cards after the handover screen, plays a turn, calls Uno at the right time, then gives the device back before the next hand appears.

Frequently asked questions

How do cards stay private on one screen?: Between turns, a handover screen asks you to pass the phone to the next player. Their hand appears only after they confirm that the opponent has looked away.
Which Uno rules does this mode use?: +2s and +4s stack separately, cards with the same rank can be chained, and forgetting to call Uno leaves you open to a two-card penalty.