The enthusiasm with which mobile operators have embraced data offload to Wi-Fi, as a way to ease the strain on their creaking 3G networks, often obscures the fact that what they are doing remains, for now, highly unsophisticated. Some cellcos have invested large sums in building their own hotspot networks, or connecting to those of partners, but beyond the clear benefit of getting traffic off the cellular system, they are not getting much return. The user experience remains clumsy, without seamless hand-off between 3G and WLan nodes; the hotspots are not usually scientifically planned to mirror the areas of most traffic; operators cannot track user behaviour once the customer has been offloaded, and so lose the chance to monetize; and…