According to http://www.ggweather.com/heat/, on average since 1998, 38 children die every year due to heatstroke in a vehicle. 51% were 'forgotten' by the caregiver.

Using bluetooth low energy (BTLE) to establish a link to the caregivers smart phone, and energy harvesting methods to provide power, the device will alert a caregiver that a child's car seat is still occupied when they have left the area.

With the power supply being supplied by a passive energy harvesting method, the device can be integrated completely into the car seat, with no need for a plug into the car's power outlet.

By using BTLE, the energy requirement is reduced, and the device becomes accessible to larger audience.