The iPico attaches to an iPhone (3GS, 4 or 4S) or an iPod Touch (third or fourth generation) with a pop-out dock connector. The iPhone slides into the dock; turn the iPico on and you're ready to go -- to the App Store, to download the required free app.
General Imaging iPico
I did have a little trouble getting everything working: The first two times I tested it with an iPhone 4, the app couldn't tell the projector was attached, simply giving a "no device found" error message. The third time was the charm, though -- with a second iPhone 4, the app and the projector found each other right away. (Out of curiosity, I also tried the app on an iPad -- which is not in the list of supported devices -- but it froze.)
Projecting from your phone
The app lets you project six things from your phone: your own photos and videos, Facebook pages, websites, YouTube videos and what the phone's camera sees. This last option lets you use your phone as a sort of projector magnifying glass, since the way the iPico fits onto the phone, the iPhone's camera will be pointed down when the image is on the wall. (You can also view Office documents, but that requires a $4.99 app called Go Universal.)
The projector's image is really too dim and too small to make it an enjoyable way to look at Web pages or Facebook feeds. At a distance of 10 feet, the image was about 4 feet wide, but was out of focus; this isn't surprising, since their specs claim only a "throw" (projection) distance of up to 5.5 feet. It's fine for quick-and-dirty displays of photos and video, however.
For example, it was easy to get a slide show going of some of our travel photos, though the projected image was stretched to make it fit the iPico's 16:9 resolution. And a college-age friend (closer in age to the happy people depicted on the iPico box than I am) suggested that someone could show friends their current video projects, or someone could take photos at a party and project them while the party was still going on.
Weighing only 3.6 oz. and measuring not much bigger than the iPhone itself, the iPico is a fun tech toy and definitely a conversation-starter. I couldn't recommend it for more serious applications, though.
The projectors I looked at fall into three tiers. The top tier includes the Qumi Q5 and the 3M MP410. Both project large, bright, sharp images, have a wide variety of source options and can deal with pretty much any file type you want to throw at them. But both need to be plugged in, making them less portable than the second group. Of these two, I preferred the Q5, even though it costs a bit more, because of its superior fit and finish.