Key ring attachable mobile phone power and control device

A portable mobile phone power and control device comprising:

• a housing having a user operable latch for releasably attaching the housing to a key ring of a user;
• a rechargeable battery within the housing for supplying power to a mobile phone having a drained battery;
• and
• electronic circuitry within the housing powered by the rechargeable battery;
• the electronic circuitry comprising a battery charger for controlling the recharging of the rechargeable battery from an external power source and for measuring the voltage of and current from the rechargeable battery;
• and an accelerometer for measuring forces exerted on the device due to user movements and for providing corresponding signals to a microcontroller;
• the microcontroller having embedded executable instructions for controlling the microprocessor to detect shaking of the device from said signals, to determine in response to said shaking a charge level of the rechargeable battery using said voltage and current measured by said battery charger, and to control an indicator on the housing to indicate the charge level to the user.