Activating an electronic device

A method of activating an electronic device comprising a processor having a motion-activation mode and an operating mode, an orientation sensor operable to detect an orientation of the device, and a clock configured to, when the processor is in motion-activation mode, periodically power up the processor, wherein the processor is configured to, when powered-up in its motion activation mode, obtain a measurement of the orientation of the device from the orientation sensor;

• store the obtained measurement;
• and process the obtained measurement in dependence on two or more stored measurements of the orientation of the device so as to determine whether the obtained measurement and the two or more stored measurements are indicative of a predetermined sequence of at least three orientations of the device, the method comprising:
• providing instructions to a user to perform a predetermined sequence of orientations of the device;
• when the processor is in motion-activated mode, performing the predetermined sequence of at least three orientations of the device substantially as instructed;
• the processor obtaining a plurality of measurements of the orientation of the device from the orientation sensor and processing those measurements to identify the performed predetermined sequence of at least three orientations of the device;
• and
• causing the processor to transition from the motion-activated mode to the operating mode.