Hello,
When creating a custom challenge you can only use longest activity, fastest effort, or total activity as the benchmark for the challenge.
However, having the ability to create a challenge based on a X number of activities in Y amount of time would be great, for ex. Complete 100 rides or runs in a year, or 15 activities in a month, etc.
It came to my mind after seeing a challenge of riding 100 days a year in pinkbike.com, being able to follow your progress and share this kind of challenge with someone else in Strava would be nice.
