The Apple iPad, Google Nexus and Amazon Kindle Fire tablets all lack one important feature: expandable storage. If you buy a slate with, say, 16 GB of on-board flash, there's no way to upgrade. Granted, this might not be a big deal in an era of cheap and plentiful online storage services, but expandable storage is nice to have, particularly if you work with large volumes of data and frequent areas with spotty Wi-Fi or cellular coverage.
So which slates are expandable? Microsoft's Surface RT and Surface Pro each have a microSD card slot that provides up to 64 GB of additional storage. The HP Slate 7 has a microSD slot and also can be upgraded to 32 GB of storage. The same goes for several Samsung tablets, including the Galaxy Note 8.0 and Galaxy Tab 2 7.0, as well as the 10-inch Acer Iconia A200-10g32u.