Sharing a card
A card hands out two links, and which one you send decides what the person opening it sees. Sending the wrong one is the one mistake worth being careful about.
The invite link
This is the card's own address, noya.so/c/YOUR_WALL_ID. Anyone holding it can read what is there and add their own card, and nothing is held back from someone who has never used Noya before: no account, no app. Send it wherever the people you want to hear from already are: the group chat, the team channel, an email round the office.
The delivery link
The same card with ?view=recipient on the end. It opens with the card's title and one button, and behind that the cards: no way to add anything, no tool rail, nothing to change. Send it to the person the card is for, once it is full.
Keep the delivery link away from them until you mean it
The delivery link is the moment the card was made for, and a moment only happens once. Keep it out of the group chat, the shared channel and anywhere else the person it is for can read. What goes round for people to write on is the invite link, every time.
Checking it first
Preview, in the tool rail, opens the card the way the delivery link will open it, so you can read it as they will before you send it. Coming back out of preview puts every control where it was.
The square
Each panel also draws a QR code for the link it is offering, which is the shorter way to get a card onto somebody's phone when you are standing in front of them.
Who can see a card
Anyone with the link. Cards are unlisted rather than private: they are not indexed by search engines and cannot be browsed, but a link that gets forwarded works for whoever receives it. Treat a card as visible to everyone it has been shared with.