— Barnes & Noble Nook HD (starts at $199 for 8 gigabytes of storage)
Barnes & Noble has paid a lot of attention to the screens on its Nooks. This year, it's clearly outdone the competition, with a screen that packs the pixels tighter than any other small tablet. It's very sharp and colorful, approaching the look of the Retina screen that graces the full-size iPad.
The other strength of the Nook HD is that it has a slot for a memory card, meaning that you can expand the storage space for movies and music by 32 gigabytes for $25. It's the only tablet in our roundup with this feature.
The downside is that the Nook HD is less of a general-purpose tablet and more of a consumption device for books and movies. It doesn't have a camera, so it's no good for videoconferencing. The selection of apps is the smallest. You'll find big names like "Angry Birds" here, but there is no depth to the catalog. There's also no option for cellular broadband.
Still, the Nook is an excellent choice for avid readers, kids and others who won't be frustrated by the small selection of things like 3-D shoot-em-up games.
— Google Nexus 7 (starts at $199 for 16 gigabytes of storage)
Frustrated that Amazon and Barnes & Noble were taking Google's Android software, gutting it and using it to power tablets that don't yield the search giant a red cent in advertising revenue or e-book sales, Google this year launched the first tablet under its own brand. The Nexus 7 has a power-house processor and a screen similar to that of the Kindle Fire HD. Since it runs stock Android, it has access to hundreds of thousands of applications written for Android smartphones, and it has more sophisticated multi-tasking abilities than the competitors, so it's easy to switch from program to program. Like the iPad Mini, it has a GPS chip for navigation. It has a front-facing camera for videoconferencing.
There's a $299, 32-gigabyte version that can connect to AT&T's wireless network.
The Nexus 7 is a great tablet for the technophile who would chafe at the restrictions imposed by competing manufacturers. But anyone will be able to appreciate it. In terms of kid-friendliness, it's beaten by Amazon and Barnes & Noble.
Peter Svensson can be reached at http://www.twitter.com/petersvensson