Transcript for The Do's and Don'ts of the Dating App Tinder
Yeah, that's a no. Reporter: Alyssa here is deciding, often in less than a second, whether she finds a slew of guys attractive or not. So, this is you rejecting them. No, no, this me swiping through all of their pictures. And then -- That's the rejection. Mm-hmm. Reporter: Just bang, like that. Steven is doing the same. It's ridiculously simple. Reporter: It is ridiculously tinder. It's revolutionary. It's all about the way you look, period. Online dating sites like match.com and e-harmony promise "Ms. Or Mr. Right," but first a long questionnaire. Tinder offers Ms. Or Mr. Right now with as little background information as possible. I just feel like my generation, there's an app for it. And it's instant. Yeah. It's not that your lazy? It's just this is available to you so why would you do it any other way? Exactly. Reporter: Swipe right on a photo if you like it. So she's cute. Reporter: Swipe left if you don't. Just a bad vibe? Yeah. Reporter: If you both swipe right? Just got a match. It's a match, you message, maybe meet, maybe more, maybe marriage. You have hooked up with girls through tinder? Your mom's not watching. Yeah, I have. Are we talking once or twice, or are we talking 65 to 70 times? Um, let's just say I have. How many matches have you had on this? Let's see. 1,775. That's a lot. Yeah, it is a lot. Reporter: All the cool kids are doing it. 1.3 billion swipes every day -- according to tinder's founder and CEO 28-year old Sean rad. All this swiping has landed him cover boy status on this month's Forbes magazine. You're just the modern day Hugh Hefner, promoting sex. Selling sex. Right? No. We are making it incredibly easy for two people to meet. What they decide to do with that is up to them. Reporter: Meetings based on four photos and maybe, maybe a one line blurb. Star signs, favorite movies, favorite food, whether you like George Michael or not, I mean, that doesn't matter? It matters in the long run maybe. But when it comes to developing that initial impression, we don't believe that that is necessarily the most important factor. Reporter: We hate to admit it as a species, but looks probably matter most. You look at one photo. Sure, sure. Which is kind of caveman? It's efficient. Somebody told me the other day that he's been exposed to more women in the last year than probably his ancestors have in a lifetime. Reporter: Rad boasts he met his own girlfriend on tinder. He swiped right, and he matched heiress Alexa Dell, daughter of billionaire computer magnate Michael Dell. He was lucky. It's a very simple idea? Simplicity is sometimes very complicated. Reporter: If the balcony scene from "Romeo and Juliet" was the old sex -- See how she leans her cheek upon her hand. Reporter: Then, tinder is the new sex -- half of its users are between the ages of 18 and 24. I know when I don't like someone. I can tell immediately. Reporter: It's just gut intuition? Mm-hmm. Reporter: Alyssa, by the way, made a match, set a date. I really don't know that much about him. Reporter: We'll get back to that a little later. Tinder has penetrated society so deep, popular video bloggers like Chris Thompson are ranting about it on youtube. For every shirtless On there, there is a duck-faced idiot girl. Me and my grandma. Dude, perfect. I respect women, love my grandma. And, have you had bad dates? Oh, yeah! 'Cause there's one thing that tinder can't do, and it can't tell you if you have chemistry with somebody. Reporter: No chemistry equals bad date. And ticked off tinderites aren't afraid to post intimate details of dates gone awry on websites like instagram and Reddit. And just this week, this nosy new Yorker couldn't resist live tweeting excruciating details of a tinder date at the next table. It became pretty clear early on that it was a first date. She tweeted, "Sitting next to the most obnoxious tinder couple ever." "Dude just casually admitted it's his third tinder date of the day." He was very proud of not only been on tinder, but having been a bit of a master at tinder. Reporter: It gets worse. "He's swiping though tinder while she's in the bathroom." He was swiping to the right the whole time. I was amazed. I thought it was so obnoxious. Reporter: Our boy Chris is hoping for a better outcome. He's made a match. She's late. If she doesn't show up, that's okay! Reporter: Back to Chris in a minute. But first, is this superficial sorting actually the way to go? Physical attraction is critical, it really is critical. It doesn't keep a marriage together, but it starts a marriage. Reporter: Sociologist jess carbino lectures at Loyola marymount and, she moonlights as a paid consultant, analyzing tinder behavior. Are these kids dating differently than, you know, I did ten years ago, than my parents did? I think that young people are definitely engaging more in a hook-up culture than they have been historically. Reporter: Now, there are, of course, some tinder dos and don'ts. If you do a mirror picture with the phone. It's absolutely no. Reporter: Bawdy talk, too soon, is often off putting. Oh my goodness. Yeah. That's pretty forward. Uh-huh, and that's his first message too. We can't even tell you what that guy said. Reporter: Posting pix with cute friends is actually a good idea. There's the effect of when you're posting with another person, and they're more attractive then you, they make you look more attractive. Reporter: Which brings us back to Chris and his tinder date. Well, she's about 25 minutes late. Maybe she was just getting extra pretty for me. Reporter: The lovely Dana is a show. Hey! How are you? The hardest part when it comes to tinder, is that you don't know if they're going to be how they represented themselves and she did. She's awesome! He's got a great personality, super sweet, and I thought we'd have a lot in common. Reporter: And Alyssa's date Brian showed up too. And so did I. Seems to be getting on. He's relatively good looking, you both matched. What did you like online about each other? You know what, I didn't put much thought into it. Really. Jeez! Wow! Reporter: And why did you swipe yes on this guy? His blue eyes. The blue eyes, the dark features, tan. Reporter: Yeah. The blue eyes are working for you. Definitely working for you. Reporter: Alyssa telling us she found herself a good one. So what do you think? I think he's really cute. Reporter: Yeah? Yeah. Reporter: This could be tinder working? This could be tinder working. Reporter: Is our smart phone now in charge of our sex lives? We're certainly yielding a lot of control to our smart phones. Sure, absolutely. Reporter: My phone now controls my sex life. In, in a way, yeah. So, have you used tinder? Let us know, use #abc2020.
This transcript has been automatically generated and may not be 100% accurate.