They can be used from the first day baby is born, all the way until sitting (around 5 - 7 months), crawling (around 8 - 10 months), and beyond.... (mamaot.com)
We recommend using the Baby Shusher from the first day your baby is born. (babyshusher.com)
You can try baby massage really early, actually from the day your baby is born. (easybabylife.com)