Twitter/Yoky Matsuoka
Matsuoka joined Apple last May to work on Apple's heath technology efforts, but she left towards the end of 2016.
Prior to joining Apple, Matsuoka was a VP at smart home business Nest, which was founded in 2010 and bought by Google for more than $3 billion (£2.4 billion) in 2014. She was one of the earliest employees at the firm, which lost its founder and CEO, Tony Fadell, in June 2016.
Matsuoka originally left Nest in 2015 to become CEO of a health data startup called Quanttus.
In her new CTO role at Nest, Matsuoka will aim to help define a long term product road map for the company, according to Bloomberg. She'll reportedly work with Nest's engineers and product teams to identify how the latest breakthroughs in fields like AI can be embedded into Nest's thermostat. She'll also actively seek outside companies to partner with.
Matsuoka, who studied at Harvard, MIT, and Berkeley, also cofounded X in 2009, the Alphabet research lab that spawned Google's self-driving car and Google's augmented reality headset, Glass.