People of a certain vintage will recognise the old style ‘three rings’ as being the renowned way to signal you’re OK or you’ve got home alright without wasting your 10p by connecting a phone call.
The 3rings plug simply sits in the socket behind any regularly used electrical appliance such as a kettle or TV. The plug rings a smartphone telling it that the kettle, for example has been activated in the expected timeframe – and so everything’s right with the world. Simple, unobtrusive and clever.
From: www.3rings.co.uk
Price: £79 (plus subscription)