For a few months I was running a friendly cooperative group challenge with colleagues. I set up a club for my workplace and invited people that wanted to join. The group challenges were a great way to get people involved, people were keen to know just how far as a team we could go in any given month. It was a great motivator for people to be healthy
Unfortunately, I had to stop a few months later, as non-premium members only get to join 3 group challenges, you have to be a premium member to join more. This is the most artificial barrier I have witness in freemium apps. Maybe I'm missing something but its not like cash prizes can be won in group challenges, its just a virtual leaderboard that can be aggregated in different ways.
Its really disappointing, and I would like to see better support for creating Stava groups for workplaces.