What is the maximum length for a list name?
List names can be up to 200 characters long. If you type or import a longer name, 2Do shortens it to fit automatically — nothing else about the list changes.
On a CalDAV server
CalDAV servers cap the display name of a calendar, so when 2Do writes a list to a CalDAV account (iCloud, Fastmail, Yahoo, Fruux, Nextcloud, or any custom server), it sends a 25-character version of the name.
This only affects what the server stores. The list keeps its full name in 2Do, and the shortened server copy is never written back over it, so nothing you see in the app changes.
If you want the name to read the same in both places, keep it to 25 characters or fewer.
Emoji and some symbols count as more than one character toward both limits, but a name is never cut in the middle of an emoji.