Around back is a Feather Huzzah that receives step data from the phone and drives a strand of side-lit LED strips. There’s a Hall effect sensor in the tail, and Slither is powered on and off ...

It started in 1965 in Tokyo, Japan, where a company released an early step counter, calling it manpo-kei, or 10,000 steps meter. The marketing suggested this number of steps would reduce the risk ...