Attachments, formatted text and mentions

A card can carry its files – the flyer draft, the photo of the hall, the signed offer – and its description and comments can be formatted. Mention someone with @ and they are notified.

Attach files

Open the card → Attachments → Add file. You can also drag files onto the card details or paste a screenshot into them. On a phone, Take photo opens the camera.
A file can be up to 10 MB on the Free plan and up to 100 MB on paid plans. An organization stores up to 1 GB on the Free plan, 250 GB on Team and 1 TB on Business; the card details say when the storage is almost full.
Programs and scripts (for example .exe, .bat, .js) cannot be attached. What a file is, is read from its content, not from its name.
Pictures get a preview; click it to see a larger one right below the file. Open shows a picture or a PDF in a new tab, Download saves the file.
A card shows the number of its files on the board.

Location and camera data are removed from photos

Photos often carry the place where they were taken (GPS) and details of the camera. Contals removes them from JPEG, PNG, WebP and GIF files while they are uploaded, before anything is stored – the picture itself stays as it was, only its rotation is kept. That matters for churches and clubs that share photos of children.

Photos in HEIC, TIFF or RAW formats are refused, because their metadata cannot be removed reliably. Save them as JPEG first (on an iPhone: Settings → Camera → Formats → Most Compatible takes JPEG photos from then on).

The cover

The first picture you upload to a card becomes its cover, shown at the top of the card on the board. Make cover and Remove cover on a picture change it; the card’s creator and editors can do that.

Who can do what

Everyone who can open the board sees its files and can download them – viewers and guests included.
Contributors, volunteers, editors and admins add files. Whoever uploaded a file, and editors, rename and delete it.
Deleting a file removes it for everyone on the board; the stored file is erased a day later.

Formatted text

Descriptions and comments can be formatted. Click into the description and the toolbar appears: Bold, Italic, Heading, Bulleted list, Numbered list, Quote, Code and Link. Shortcuts work as you know them: Ctrl/⌘ + B for bold, Ctrl/⌘ + I for italic, Ctrl/⌘ + K for a link; typing - starts a list and ## a heading.

The description is saved when you leave it (or with Save); Cancel keeps the earlier text.
A comment is sent with Comment or Ctrl/⌘ + Enter.
Links must be web addresses (https://…), e-mail addresses (mailto:…) or phone numbers (tel:…). Links open in a new tab.
In the simple view the toolbar shows only bold, bulleted list and link.

Texts are stored as Markdown, so a description keeps its formatting in exports, in the API and in an import from Trello.

Mentions

Type @ in a description or a comment and pick a person from the small list – only people who can open the board are suggested. The person is notified as Mentioned in the inbox, under For you on the home page and, depending on their settings, by push or e-mail (notifications).

A mention does not give anyone access to the board.
Volunteers, viewers and guests can be mentioned too.
A mention always shows the person’s current name; when someone leaves the board, their mention shows “former member”.

Two people editing one description

When someone else changes the description while you are editing it, a note says so and lets you look at their version. If you save anyway, your text wins – and their text is kept below the description, where any editor can Use this version or Dismiss it. Nothing is lost silently.

Files on confidential boards, exports and moves

Files are stored in Cloudflare’s EU jurisdiction, like the rest of the board, and opened through a separate address with links that expire after 10 to 20 minutes: a file never runs as a page of Contals, and a link that is passed on soon stops working.
On confidential boards the links carry no file names.
Board admins download all files of a board as ZIP in the board settings under Export data; the JSON export lists them.
Moving a card to another board takes its files along. Copying a card or a board, and templates, leave files out.
A card that a retention rule deletes takes its files along.