Griply

Logging sends and grades is the easy part. The signal I would actually want is attempts versus sends on the same problem over time: a V4 that took four sessions, then a similar one that took two, says more than a list of completed climbs. The feature list mentions attempts, grades, and 'progress over time' — is that a grade histogram, a session streak, or a per-problem attempt history? Also, are gym and outdoor, or boulder and rope, separate logs? Mixing them in one feed makes any trend line pretty hard to trust.

A playful logbook is a nice angle, since most climbers I know just keep notes or a spreadsheet. Have you considered tracking attempts per problem alongside sends, so people can see how many tries a climb took as they improve? That would make the progress view feel a lot more personal.