Ask someone to describe what a tapping toy does and you get a lot of hand gestures.
Here is the short version: instead of a motor buzzing against you, the head taps. Rapid, repeated, in one place. People who go numb on vibration after a few minutes tend to find tapping keeps working, and that is the whole reason this is its own category now rather than a footnote on the vibrator section. Rechargeable, waterproof, body-safe silicone.