In 2012 new NCAA rules allowed unlimited contact by coaches via calls, texts and social media (direct messages only) to recruits who have completed their sophomore year. The electronic correspondence must wait until June 15 after their sophomore year is completed. If the prospect is still a sophomore in high school or younger, there should be no calls or text or DMs to that prospect.
When it comes to official visits, juniors in high school now can begin to take official, paid visits starting Jan. 1 of their junior year. College coaches can even have contact with a junior along with an evaluation in his junior year at his high school only.
Basically the NCAA has opened the communication lines so prospects and coaches can better get to know each other and try to build a meaningful relationship. The date to remember is June 15 following the completion of the prospect's sophomore year.