No, it's not ok.
What you do is think about your child in general. Is he doing well in school (performing to the best of his abilities, showing up to class on time, not receiving detentions or suspensions)? Does he seem reliable overall, like does he say he'll do a particular chore like mow the lawn by Saturday, and by Saturday he has mowed the lawn? Does he respect the curfews or time limits you have set?
And then you think about your neighborhood. Does he have things to do, like skateboard or go to friends' houses to play video games, or is there a basketball hoop, or is he just sitting in the park with nothing to do?
If he's trustworthy and if he has something to do besides hang out in a 7-11 parking lot, then give him some freedom. Spying on him will lead to problems.
You set boundaries. Clear, concise boundaries. Not "be home before supper" but "be home by 7 pm". And you remain vigilant. If he comes home and he's been smoking or drinking, or if he suddenly has super-expensive electronic gear that he ordinarily could not afford, then you set stricter limits or remove privileges altogether. And you establish logical consequences. If he isn't home by the time limit you have set, he loses the privilege of freedom. If he loses his valuable skateboard or phone, you don't buy him a new one. He has to earn it. And don't be afraid to tell him that you worry, but also tell him that he can earn your trust and respect and privileges by remaining honest and accountable.
And he should have a basic cell phone - one without internet capabilities. Just one that makes and receives calls, with maybe a few functions like an alarm clock. Establish some rules. Figure out a way for him to call you if he ever finds himself in a difficult situation, like someone has been drinking, or a fight is about to break out. I know I've said it before on here, but I gave my son a code. If he felt unsafe, or if kids were about to drink and drive, he was to call me with a fake message if he wasn't free to speak in front of his friends. He was to say something like "oh, I forgot to tell my mom a phone message and she freaks out" and then he was to call me and say "mom I forgot to tell you that Uncle Ed called and Aunt Edna is in the hospital" (and there is no Uncle Ed or Aunt Edna). That was my cue to ask yes or no questions. Is someone drinking? Is the person who drove you to the movies drunk? Is a major brawl about to break out? If the answer was yes, I would 'freak out' and ground him and come get him, allegedly punishing him for not telling me Aunt Edna was in the hospital. He was rescued, I was the bad guy. No questions asked. I'd come get him at any time.
We also had a quick "check in" code. We still have it. It is R U A & W. I type that to him. It means Are you alive and well. He texts back A & W. He knows if he doesn't respond, I will hound him and blow up his phone with texts (well, not anymore since he is employed and an adult, but I used to threaten to do that when he was in high school) and he would lose privileges. Now I only text that if he is on a long road trip for his job, and he's driving through the night to get to an event. He doesn't text while driving, but he has a talk-to-text thing and he just tells his phone to tell me that he's A & W. You can establish something like that with your son, and tell him that you don't need to know everything that he's doing, but that responsiveness and responsibility and accountability will lead to more and more privileges. My son told me that the A & W thing made him realize that I worried about him but it was quick and concise enough that he didn't mind reassuring me.
Demonstrate respect, trust, and be willing to talk and listen to him, and he will live up to that. Demonstrate spying and a lack of trust, and he'll live down to that.