I recommend that your child first explore relationship in group settings. This is very natural and safer. The adolescent is preparing for responsible behavior later.
In general I recommend that anyone under 16 who wants to date needs to go out in a group. After that age, and if your child seems ready, I would give them permission to go out paired.
Then it is best to graduate to supervised dating. By this I mean that an adult drives the kids to and from their destination. Before the date, however, get to know the prospective date. Call their parents, especially if they are under 16. Making your presence known offers another safeguard for your child.
Finally, appreciate the cellphone. Cell phones make it easy for your child to check in with you and for you to call as well. However, too much hovering will only result in your child rebelling. It is equally important to give your child space to experience their growth. That for the parent requires patience and trust.