Figure 9. 27 : Kindle Whispersync UI dialog (Image by Kei Noguchi).
You’d expect this from any other connected device too. For example, your
wall thermostat says it’s 21C and the heating is on. You’d therefore expect
your smartphone heating app to say the same thing, and not to tell you that it’s
actually 22C and the heating is off.
If you turn the heating off from the wall, then you’d expect the smartphone
app to reflect that change in state right away. Right?
Unfortunately in IoT, as discussed in chapters 2 and 3, this isn’t always
possible. Devices that need to conserve power, such as those that run on
batteries, often cannot maintain constant connections to the network as this