Portable projectors such as Acer's C20 pico projector don't tend to vary much from a design perspective; by the time you've slapped together the necessary components for lens, input and a reasonably sized battery, there's not a lot of space left for custom visual features, leaving the description that most of them look like a pack of playing cards being very apt.
The C20's controls predominantly reside on the top of the projector, where you'll find the controls for adjusting inputs and display characteristics, save for the focus wheel, which sits on the right-hand side of the projector body if you're facing it directly. The C20 will take a variety of inputs. On the left-hand side, under a flap, you'll find inputs for micro USB (a cable is provided) and microSD cards, as well as an A/V input socket for iPod. On the right-hand side sits a mini-HDMI (C Type) socket, and a "universal" IO socket.
The projector within the C20 is a DLP-type with a native 16:9 WVGA (854x480) resolution, capable of up to a maximum (WXGA) 1280x800 display. Contrast ratio is stated at 2000:1, but, like most pico projectors, the ANSI Lumens rating is on the low side, compared to a traditional full-bodied projector — this one is rated at only 20 ANSI Lumens. For practical purposes, this means that you can use it in a lit room, but only just, and really only because the practical throw distance of the projector isn't all that far in real terms.
It may have just been our review sample, but the supplied documentation with the C20 isn't that impressive; a slender multi-language "quick start" guide that's dwarfed by the warranty cards that come with it. What the quick start guide does suggest is that, with the right cables, the C20 should be a rather flexible projector depending on your needs.