It used to be said that what goes around always comes around again in technology, as when old fashioned bureau based utility computing returned under the banner of cloud. Now it is happening in the case of tablets with a comeback for cellular connectivity, which was promoted as a selling point in some of the first models including early iPads. In truth mobile data connectivity never really caught on for tablets a few years ago and was largely confined to smartphones, with about half of tablet users failing to activate their connections at all with their service providers if this was available. At that time, around 2011, about half of tablets sold were in turn cellular enabled, which meant that…