It was a weekday afternoon when Jenny heard a ping on her phone, and saw the screen light up with a message from Dan. She had ‘liked’ him on the dating app Tinder a few days before. Now she was at home in her yoga pants, with no make-up, bored, and she liked the look of the dark-haired guy on her screen.

Jenny’s in her 30s. A pretty PhD student with wavy brown hair, she could easily meet someone in bar. But now, in the afternoon, she fancied a bit of flirting. So she sent Dan a text. And they began chatting. The small talk got more personal and raunchy. “I’m only looking for sex,” Dan said.

“That was cool with me,” Jenny tells me now, grinning. “I thought he was hot. He seemed nice, he worked for a major financial firm, I just thought, why not?” Tinder is “just for casual sex and hook-ups,” she says breezily. “I’m not interested in a relationship. I prefer this to online dating”. It’s “more discrete” she thinks. She travels a lot. For her, phone apps are a convenient way to meet men.

Dan started texting things he wanted to do with her. Getting excited, she replied. They talked about going to bed. They talked about getting a hotel room. Jenny suggested meeting. Suddenly Dan texted: “I’ve got to go. My boss just walked in!” “I couldn’t believe it! That’s the only problem with phone apps,” she giggles. “You never really know what’s going on with them.”

The rise of the dating app

Once, there were singles ads in newspapers; our generation was the first to take our lonely hearts online. Now, the rise of smart phones has ushered in a new dating era: that of mobile dating apps, which match singles with other singles who are close by, thanks to GPS technology. Around the world, mobile dating apps have sprung up: Tinder, Grindr, Blendr, Pure, BeNaughty, Tingle, SinglesAroundMe, Bang With Friends, F-Buddy. And as some of their names suggest, these apps aren’t just offering a new way to date: they’re changing the way we date too.

At first, “dating apps were almost exclusive to gay men. When Grinder launched in 2009 it quickly earned a reputation for promoting easy hook-ups rather than long-lasting love. At the time, the consensus was that women would never use apps to ‘hook-up’ in quite the same way. After all, society tells us women are choosy, we’re romantic, we’re emotionally engaged and sexually demure. We are dreaming of love, marriage, babies and finding The One – not having one night stands. And yet – despite such reasoning – use of dating apps to hook-up has flourished amongst women.

Blender, perhaps the best known app (which, as its name suggests, mimics the format of Grindr), launched in 2011, and according to its founders, straight daters picked it up immediately. In Australia, the latest success story has been Tinder. Since launching here in September, it has grown by five per cent daily; worldwide, it makes 2 million matches a day. And women are using these apps just as much as men: Tinder boasts its users are a 50/50 gender split. Tingle, also available in Australia, has a similar mix. Even the apps with names that suggest they’re explicitly for hook-ups – such as F-Buddy, which has 300,000 Australian members – has plenty of female members. (The number of Australian women on F-Buddy increased by a third last year.) That women are using these apps in greater numbers is empowering, suggests Dr Paige Padgett of the University of Texas, who has studied online and mobile dating. She sees it as proof that women are “embracing sexual technology to get what they want”.

Others aren’t so sure. Some have raised concern over the safety of dating apps. Still more worry about teens accessing them and feeling under pressure to engage sexual acts they wouldn’t otherwise (either in real or virtual life). What’s in no doubt is that the rise of mobile apps is changing the dating scene and challenging our beliefs about what women want from it.

Of course, not everyone using mobile apps, such as Tinder, are looking for casual sex. For plenty of women, dating apps are simply a natural progression from online dating – a more convenient way to meet men. “I’ve dated guys I’ve met on Tinder”, Laura, a 23-year-old marketing trainee, told me flicking her silky brown hair as we drank juice. “I wouldn’t use it just it for hooking-up. I think of Tinder as classier, not just a way to have a one night stand.” Because Tinder links to your Facebook, flagging up mutual friends you have with your matches, and you know everyone on there is single, Laura considers it’s a better way to find a compatible boyfriend that just waiting to meet someone through friends or while out at night.

Not everyone has such clear-cut expectations. Amy is 24 and a very pretty, sparkly, blonde journalist. She's confident, chatty and certainly not shy about meeting up with people for dates. She recently joined Tinder, and this week went on her first date – and met him for lunch. “He was really sweet, really good-looking, I really liked him and thought we might hang out again sometime.” That night she was out with her friends having a few drinks when she decided to message him: “Do you fancy coming to mine?” He did.

Says Amy, “My friends keep saying I used Tinder to hook-up, but it wasn’t really like that. I mean we did go on a date first. I dated him really... then we just ended up in bed". Will she see him again? "Maybe" she said unconvincingly.

It’s this blurring of the lines between what constitutes ‘dating’ and what constitutes ‘hooking up’ that may be the lasting legacy of mobile apps, according to some experts.

Changing the way we date

Dr Padgett believes that apps are fundamentally changing the way we date – and making it more likely than singles – even if they’re ostensibly logging on to find ‘The One’ – will hook up instead. In her studies of online dating she found that women’s intimacy with partners was “accelerated” when they met online. She put this down to the speed at which the net enabled people to meet and communicate with potential partners. This speedy-bonding translated into the bedroom, with 30 per cent engaging in sexual activity the first time they met. Padgett suggests apps, by operating even faster, potentially enable faster ‘bonding’ still. Another US study found that 60 per cent of singles said that using a mobile dating app made it more likely they would hook up.

Anita is a teacher in her mid thirties; she’s cute, a bit of a gym-bunny. She’s been using Tingle for more than a year meeting tech-nerds, real estate guys, and quite a few hipsters. “Too many hipsters,” she laughs. She had left the site for a while but recently reactivated her account, “It gets addictive fast,” she admits. She would like to meet someone but meanwhile, she grins, she’s “not going to deny hook-ups happen”.

She is chatty and casual talking about how she uses Tingle. She meets dates in a public place and doesn’t give out her number either “until I know they’re respectful of boundaries” and tends to meet her dates in a bar, coffee shop or when she’s out with friends just “to kind of add some intrigue to the evening”. Anita admits she’s had “many a Starbucks rendezvous”. If there are sparks with her date she’ll invite them back to her place. Her best experience? She laughs. “It’s too specific to share! Suffice to say we were kissing within six minutes of meeting face to face.”

Anita believes that part of the reason that apps such as Tingle have become so popular is because they put women in control. Unlike in a bar where you don’t know who’s single, on the app it’s clear, she points out. Plus, she says “the whole pantomime of going through the bar pick-up just bores me to tears”, she shrugs. “It makes going out with the girls more fun now because there’s no pressure! You can go home and a guy is one message away”.

How safe are dating apps?

Some people have expressed fears over the safety of meeting strangers via dating apps and going home with them. Dr Padgett worries that the instantaneous nature of mobile apps “may affect a woman’s ability to screen her potential partners”. We may act more spontaneously, perhaps rashly, and move too fast.

Ian Andrew Bell, the CEO of Tingle, says safety was a key consideration when creating Tingle – and he believes that this is part of the reason the app’s been so popular with women. The first thing Tingle did was create “systemic disincentives to discourage men from indulging in behavior that drives women away”, he explains. If you flood people with message you’re penalised. If you’re good (uploading photos, sharing where you are), you get rewards.

At the same time women can blur their location. Anita says using an app makes her feel more “in control” than meeting random men in a bar. “If I don’t like a guy I can block him. I have done that a lot.”

Yet despite her enthusiasm for app dating – and hooking up – Anita, like all the women marie claire interviewed for this story, didn’t want to use her real name. She admits that she doesn’t necessarily share her experiences with her friends. “People are still judgmental.”

In a society still uncomfortable with the idea of women having casual sex, Dr Paige Padgett believes that part of the reason for mobile apps’ success is the anonymity they give women. ‘It gives women the freedom to ‘put themselves out there’ sexually”, she says.

There are other perks: “We are a time-poor culture”, says Dr Padgett, “the 24/7 accessibility of the Internet is now in the palm of your hand. A woman can negotiate and explore her potential partners from her phone on her time frame and schedule”.

The fourth wave of feminism

Does it feel surprising to hear a woman talk so frankly about sex? Don’t we all with our friends? This isn’t the Fifties; one-night stands are hardly shocking or rare. The interesting question the boom in sex apps raises, is whether they’ve encouraged or facilitated this? Which came first: the hook-up or the app? The experts are divided.

Neal Patterson, managing director of F-Buddy, says that “the rise of fourth wave feminism” and the way it’s encouraged women to embrace sexual freedom has prompted the rise of sex apps.

On the other hand Robert Weiss, an author on books about the relationship between digital technology and sexuality, believes it’s the apps that have enabled women to have discrete, casual sex. “Young women are more likely to attend college, are marrying and having children later… and typically make more money when they graduate and enter the workforce. Hookup apps actually play a part in this, as they allow young women to enjoy casual dating and sexual hookups without the time-consuming burden of a serious boyfriend. The young women of today are just as likely as a man to say, after a date or sexual hookup, ‘It’s been fun, but now I’d like you to leave because I’ve got more important things to do than you’.”

The simple truth, he says, is that digital technology has wrought major change in every area of human existence. “Intimate relationships are no exception.”

It’s not all good news. Over at Rochester University, Marie-Joelle Estrada believes that hook-ups are not, in truth, very satisfying for women: “Most of the research and feedback I've read on the hookup culture suggests that women, on the surface, envision "hooking up" as being empowering in that they can have sex without any emotional strings attached, "just like men".

No-strings can get messy

Unfortunately the research also shows that’s not quite how it plays out. “Whereas the previous double standard was that women weren't allowed to have casual sex, the new double standard seems to be that women aren't entitled to sexual pleasure if its a one-time hookup. Men appear to regard a relationship partner as more deserving of their time and attention in the sexual arena, whereas a casual partner is more about their own experience. Research suggests that women tend to give more in terms of sexual behaviors, and receive less from their male partners”. Ultimately Estrada casts hook-ups as a compromise. She sees them as “almost like a fast food version of dating. You may want the gourmet meal, but when you're busy and on the go, it’s not always possible”.

“It’s true”, one girl Zara told me who’d dabbled in dating and hooking-up through apps, “in the end I stopped bothering”. Not because she felt cheap or because she’s especially romantic, she said. Instead she described how she got to a point where there were too many men – too many pictures flashing on her phone, too many messages, “there’s too many choices. You meet people and you never see them again”, she said reflectively, “and in the end you don’t feel like you’ve really got to know anyone at all”.

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