Google-owned thermostat Nest opens up to external developers

Imagine a home where if you asked your thermostat to change temperature it would, or one that would text your neighbours if an alarm went off while you were on holiday, and knew when you were on your way home from work so would set the temperature accordingly.
These scenarios are all now a reality because of a move by Google-owned thermostat company Nest, which has opened up its software for third-party developers to use for the first time.