(repeating this from a beemail)
It’s basically one of those clicky tally counter devices, with Beeminder integration, i.e., it’s easy to send your tally to any Beeminder goal.
That functionality is also built in to the Beeminder Android app (aka Beedroid). I’m sometimes tempted to switch from Android to iPhone but have always rejected the idea because I’m very attached to being able to count my pushups by touching my nose to my phone on each pushup. So now I have one less excuse.