(Telecompaper) Google-owned Nest, a vendor of smart home products and services such as thermostats, smoke and CO alarms, has entered into an agreement to buy home camera and motion sensor tag company Dropcam for USD 555 million in cash, subject to adjustments. Dropcam was founded by CEO Greg Duffy and Coo Aamir Virani in 2009. Its backers include Accel Partners, Kleiner Perkins Caufield & Byers and Menlo Ventures.