Google is branching out in the wearable technology market, with the release of a software development kit.

It would allow developers to create wearable devices such as smartwatches and fitness trackers using the Android operating system.

Google's senior vice-president of Android, Chrome and apps said: "We want to develop a set of common protocols by which they can work together."

The kit would be available in two weeks' time, Sundar Pichai added.

Samsung's Galaxy Gear smartwatch did run a version of Android - but after concerns over its interface and battery life, it switched to the Tizen software platform for its latest watch, the Gear 2.

Google Glass is the company's main foray into wearables so far. The device includes eyeglass frames equipped with a camera and small display controlled by voice command. The product is not yet on general sale but is being tested by selected people.

"Google is taking wearables seriously and it wants everyone else to," said John Delaney, vice-president of mobility research at analyst firm IDC.

"The industry thinks wearables is the next big thing as sales of smartphones start to plateau in developed markets and this is the latest attempt to build momentum behind it," he said.

"Google would be a competitor in the market but also an enabler if it helps Android developers."

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