By Stefan Schultz

Imagine controlling your household appliances via your iPhone. Start-up companies are offering new software to enable households to boost their energy efficiency. It’s a potential mass market which is also awakening the interest of giants like Microsoft and Google.

The energy sector has a new fashion trend: the iPhone-App. eQ-3, a German company, has designed a program that controls windows, radiators, light switches and dozens of other household appliances at the touch of a button. US start-up Control4 offers a home management system that automatically dims the light when you’re watching a movie or blocks your PC and TV when the kids are doing their homework — this program too can be operated through iPhone and iPod Touch.