The very popular 595 shift register chip of the 74 series is used a lot by hobbyis because of its wide availability, good speed and simplicity. Just plug it on an arduino like shown in the tutorials and youi have 8 more outputs, put two and you have 16 more outputs ! (up to a lot of them actually, with only three pins !)
It is consist one coin type motor which is a Permanent Magnet coreless DC motor. It vibrates when the input is logic HIGH. It is very easy to drive and Grove compatible. Can be used in toys and cell phone modules.