Every deal can be checked, and no single device ever holds the deck.

Each phone at the table holds one piece of the key for this hand. The deck is shuffled by every phone in turn, and each shuffle comes with a proof that every phone checks before a card goes out. Your cards can be opened only with your phone's piece, and your phone sends that piece for your own cards only when you show them. A folded hand is opened only if the phone that folded it chooses to show it.

What you choose to show, and what someone can see over your shoulder.

Everyone else at the table acting together. They can tell each other their own cards, and with five or more phones in the hand they can open the community cards early.

The server acting together with another player's phone. It can let that player see their own cards before the hand starts and deal again if they are bad, and with the phone it names as the host, it can have a winning hand declared dead at the showdown.

The server showing your phone other players than the ones at the table. The table check in the table details shows this when people compare their words for the same hand. The server cannot pick words that match, only guess. Each guess costs it a whole new deal and matches about one time in three million.

The server holding up a hand. It can stall a hand or hold back a phone's message, which looks like that player went quiet, so the host may fold their hand, declare it dead or void the hand, and they lose what they put in.

The blinds. Your phone compares each hand's blinds with the levels the host set for the table and tells you when they differ, but it plays the ones the server set. Unless your phone opened the host's own link or QR straight in the app each time it joined, the levels can be the server's word, and the table check shows other words on a phone the server told different levels. Where the blinds go up every few hands, the server numbers the hands, so it can skip numbers and raise the blinds as early as it likes. Where they go up with time, the server can raise them about one level early, and the level of the first hand your phone is dealt this way is the server's word.

Hands dealt the classic way at this table. The server holds their deck order.

Your chips after a hand you were dealt the classic way, or after this phone was away from a hand for more than half an hour or came back to it at another seat. From then on, this phone's chip count is the server's word until it finishes a hand dealt the trustless way.

A modified app, and help from outside the app. A modified app cannot see cards it was not sent or change a shuffle it did not make, but nothing here stops a solver, a program playing for someone, or a partner in the next chair.