There are several excellent keyboard cases for the iPad. This $129.99 model is the one I’ve settled on, for several reasons. Its defining feature is that it sports a solar panel on its underside that charges the keyboard, so you don’t need to remember to do the job yourself via USB. But the keyboard itself is comfy enough for serious typing, and the case protects both sides of the tablet without adding too much bulk. It’s not perfect — the little nubs it uses to prop up the tablet sometimes slip out of place — but it’s helped make the iPad the most useful computer I own.