Proximity monitoring devices and methods

1. A small form factor device comprising:

a power source;

a force sensor for sensing forces applied to the small form factor device and generating force signals based thereon;

a wireless communications module powered by the power source, and

a processor powered by the power source, wherein the processor is configured to:

implement a proximity monitoring process involving periodically operating the wireless communications module to transmit advertisements;

determine whether device stationary criteria are satisfied based on force signals received from the force sensor or the absence of force signals received from the force sensor, and

if the device stationary criteria are satisfied, the processor is further configured to:

cause the wireless communications module to transmit a device stationary message; and

cause the small form factor device to enter a power saving mode in which the proximity monitoring process is suspended.

2. The small form factor device of claim 1 , wherein if the small form factor device is determined to be in motion while in the power saving mode, the processor is configured to:

cause the wireless communications module to transmit a device in motion message; and

cause the small form factor device to exit the power saving mode and resume the proximity monitoring process.

3. The small form factor device of claim 1 , wherein the device stationary criteria are satisfied if no force signals are received from the force sensor for a predetermined time period.

4. The small form factor device of claim 1 , wherein the small form factor device has a credit card type form factor.

5. The small form factor device of claim 1 , wherein the force sensor comprises an accelerometer.

6. The small form factor device of claim 1 , wherein the wireless communications module is a Bluetooth communications module.

7. The small form factor device of claim 1 , wherein if the small form factor device is determined to be in motion while in the power saving mode, the processor is configured to:

cause the small form factor device to exit the power saving mode and resume the proximity monitoring process.

8. A portable electronic device comprising:

a power source;

a wireless communications module powered by the power source;

an output device; and

a processing unit powered by the power source, wherein the processing unit is configured to:

implement a proximity monitoring process involving monitoring for the receipt of periodic advertisement transmissions from a monitored device through the wireless communications module;

if, during implementation of the proximity monitoring process alarm criteria are satisfied, operate the output device to output an alarm;

determine if the monitored device has been stationary for a threshold time period, and

in response to determining that the monitored device has been stationary for the threshold time period:

implement a power saving process in which the proximity monitoring process is suspended.

9. The portable electronic device of claim 8 , further comprising a location monitoring module, and wherein in response to determining that the monitored device has been stationary for the threshold time period, the processing unit is further configured to:

determine a monitored device sleep position using the location monitoring module, the monitored device sleep position being a position of the portable electronic device at or about a time it is determined that the monitored device has been stationary for the threshold time period.

10. The portable electronic device of claim 9 , wherein after determining the monitored device sleep position, the processing unit is further configured to:

periodically compare a current position of the portable electronic device to the monitored device sleep position to determine a current separation distance between the current position and the monitored device sleep position; and

if the separation distance exceeds a predetermined allowable separation distance, operate the output device to output an alarm.

11. The portable electronic device of claim 10 further comprising a display, and wherein if the current separation distance exceeds the predetermined allowable separation distance the processing unit is further configured to display the monitored device sleep position on the display.

12. The portable electronic device according to claim 8 , wherein determining that the monitored device has been stationary for a threshold time period comprises receiving a device stationary message from the monitored device.

13. A computer-implemented method for operating a monitoring device to monitor the location of a monitored device, the method comprising:

implementing a proximity monitoring procedure involving monitoring for the receipt of periodic advertisement transmissions from the monitored device;

raising an alarm if alarm criteria are satisfied during implementation of the proximity monitoring procedure;

determining if the monitored device has been stationary for a threshold time period; and in response to determining that the monitored device has been stationary for the threshold time period:

implementing a power saving procedure in which the proximity monitoring procedure is suspended.

14. The computer-implemented method of claim 13 , further, wherein in response to determining that the monitored device has been stationary for the threshold time period, the method further comprises determining a monitored device sleep position, the monitored device sleep position being a position of the monitoring device at or about a time it is determined that the monitored device has been stationary for the threshold time period.

15. The computer-implemented method of claim 14 , wherein after determining the monitored device sleep position, the method further comprises:

periodically comparing a current position of the monitoring device to the monitored device sleep position to determine a current separation distance between the current position and the monitored device sleep position; and

raising an alarm if the separation distance exceeds a predetermined allowable separation distance.

16. The computer-implemented method of claim 15 , wherein if the current separation distance exceeds the predetermined allowable separation distance the method further comprises displaying the monitored device sleep position on a display.

17. The computer-implemented method according to claim 13 , wherein determining that the monitored device has been stationary for the threshold time period comprises receiving a device stationary message from the monitored device.