Utility is an economic term for a person's overall well-being and satisfaction. Consumers play a role in the economy by maximizing utility, which means allocating their scarce resources, such as limited time or money, most efficiently. Utility maximization is different for every person.
You can start using it right away but it was suggested to us by our midwives to hold off until 6 weeks as pacifier use can mess with their breastfeeding latch (it's a different kind of sucking).
While most babies will start developing the pincer grasp near nine months of age, some babies may also reach the milestone after their first birthday. There is no need to worry if your baby is reaching other milestones, at a comfortable pace.