The infant swing is a simple concept. You suspend the little tyke from above, give the swing a little push, and let it sway the baby gently back and forth to calm the child. Now, let's apply a bit of robotics, multi-speed control, a speaker, and an MP3 player plug-in. You get the 4moms Rockaroo.
The other noticeable difference between the Rockaroo and a regular infant swing is that the motion comes from below, not with a couple of arms suspending the wee one. That makes it more like a high-tech rocking horse, or the tiny kid version of a mechanical bull, but with a mellow attitude.
The Rockaroo's five speeds vary from a very gentle movement all the way to insane. I made that last one up; all the speeds are really just variations on gentle. The built-in speakers and audio-in jack means parents can serenade the little one with soothing music from bands like The Wiggles and The Clash (babies love The Clash).
There are some interesting things going on under the surface of the Rockaroo. The drive train uses what 4moms calls "the world's strongest fiber," ultra-high-molecular-weight polyethylene. The material keeps the device quiet. Sensors respond to the motion of the seat and the baby to give each rocking movement a different feel. That makes it behave more like a human and less like a robot.