Unfortunately this did not happen with most fitness trackers. There's no successful reverse engineering of Fitbit's, Misfit's or Jawebone's Bluetooth protocol yet. Although the user base and interest may be much higher than that of spectrometers.
I joined the work on reverse engineering Fitbit's protocol but the encryption isn't hacked yet.
I second that! It's an unnecessary date of expiry for hardware. You see that in every fitness armband and more and more apps. In two years ahead it could end up as a useless piece of electronics.
In the past we used cloud features for offline tracking in AR applications because an iPhone 3GS wasn't capable of real time pose reconstruction. But today it seems more like a lock-in and a way to collect data. A quad-core cpu on a phone should do most tasks offline.
BTW: Surface / PixelsSnse was the most horrible purchase i / my university ever did. Bought a Samsung SUR40 in January 2012 for about 8000 €. Received it two month later. Another 3 month later Microsoft renamed it to PixelSense and stopped the development. No Windows 8, no Internet Explorer 11 Touch. We use it as a table.