Calm.com Inc, which makes an app that guides people through relaxation exercises and encourages users to breathe, has been valued at US$1 billion in a funding round led by TPG Growth, the start-up said on Wednesday. Calm raised US$88 million in the round, which included existing investors Insight Venture Partners and Ashton Kutcher’s Sound Ventures, as well as Hollywood’s Creative Artists Agency. The new cash influx brings the start-up’s total money raised to US$116 million....