One logbook for the gym, the board and the rock.
Most climbers end up with a board app that knows the board, a website that knows the outdoor sends, and a notes file that knows nothing for long. The journal is one record of all of it, and it is the thing every other part of the app reads.
A session, not a list of ticks
A session carries where you were, what kind of climbing it was, and how it actually went: how you felt, your psych, the state of your skin, and how hard you worked. Warmups, finger training and conditioning are logged beside the ascents rather than in a separate app, because they are part of the same day and the load calculations need them.
Ascents record attempts as well as sends, which is what makes a flash rate and a grade pyramid mean anything. A problem you tried nine times and did not do is data.
Plan ahead, or log it afterwards
Sessions can be created in advance and started when you arrive, or back-dated if you climbed yesterday and logged it tonight. One session is active at a time, which stops the common logbook failure of three half-finished entries from the same week.
A closed session can be reopened within a time limit if you forgot something, and edits to logged ascents keep their history rather than silently overwriting.
It works with no signal
Crags do not have reception. Anything logged offline queues on the phone and syncs the moment you are back in range, so the session you logged sitting on a pad at the boulder is not something you have to remember to type up later.