Google Inc. said that it will buy Nest Labs for $3.2 billion and is considered as one of the search engine operator's most expensive acquisition ever, according to MSN News.

Google was of Nest Labs' early investors. Google said that the company's Nest Learning Thermostat has been a "consistent best-seller," the report said.

Nest Labs' thermostat, which sells for $249 a pop, can learn how people like their homes heated or cooled. The thermostat learns a consumer's home temperature preference and adjusts it on its own.

Unlike traditional alarm systems, the Nest Protect system detects rising smoke or carbon monoxide levels, lights up yellow and speaks with a human voice the way Jarvis would speak to Tony Stark. The system gives consumers an option whether they want to turn the device off or not if there is no emergency. The Nest Protect alarm system retails at $219 comparatively higher to older smoke and carbon monoxide detectors that cost between $50 and $80.

According to Shyam Patil, analyst at Wedbush Securities, Google is already positioning itself to offer products at the household level. Patil said that Google is working on the "Internet of Things" that aims to connect homes intelligently with wireless devices through collected data via smartphone controls.

The "Internet of Things" is a global network that links computers, tablets and smartphones to other household devices such as bicycles, washing machines, thermostats and many more.

"It's a big market opportunity and it provides Google with good technology to attack it over time," Patil told the Associated Press in a telephone interview. Patil has a "Neutral" rating on Google shares.

Nest Labs is a Palo Alto-based company founded in 2010 by Tony Fadell. Fadell is considered a gadget guru who helped design the iPod and original iPhone while he was still working at Apple.

Google Inc. is based in Mountain View, Calif. Its shares fell $7.20 to $1,122.98 on Monday and rose $6.02 to $1,129 in aftermarket trading, the report said.