Meditation app unicorn Calm wants you to doze off to the dulcet tones of actor Matthew McConaughey’s southern drawl or writer Stephen Fry’s English accent. Calm’s Sleep Stories feature that launched last year is a hit, with more than 150 million listens from its 2 million paid subscribers and 50 million downloads. While lots of people want to meditate, they need to sleep. The seven-year-old app has finally found its must-have feature that makes it a habit rather than an aspiration. Keen to capitalize on solving the insomnia problems plaguing people around the world, Lightspeed tells TechCrunch it has just invested $27 million into a Series B extension round in Calm alongside some celebrity angels at a $1 billion valuation. The cash will help the $70 per year subscription app further expand from guided meditations into more self-help masterclasses, stretching routines, relaxing music, breathing exercises, stories for children and celebrity readings that lull you to sleep. The funding adds to Calm’s $88 million Series B led by TPG that was announced in February that was also at a $1 billion valuation, bringing the full B round to $115 million and Calm’s total funding to about $141...