The R11 tablet, made by Fremont, Calif.-based GammaTech, recently was upgraded to serve as a 2-in-1 with the addition of a detachable keyboard—which, naturally, is pretty heavy-duty itself.

as tablets paired with a detachable keyboard came into vogue. The success of Microsoft's Surface Pro series paved the way, while Lenovo, Samsung, HP and even Apple have been among those that ...