Not since the introduction of the contraceptive pill in 1960 has anything, surely, affected people's sex lives more than dating apps.

But what you might not know is that apps like Tinder, Grindr and Happn are linked to a rise in STI's that led one NHS sexual health clinic to set up what they claim is Britain's only service offering support for app users.

The 56 Dean Street sexual health clinic in Soho, part of Chelsea and Westminster Hospital, incredibly sees around 13,000 people each month - 7,000 of which are homosexual men.

Embedded into the Wellbeing Programme is tailored support for people using apps in response to the growing phenomenon of people seeking sex on their mobiles.

'You might find yourself in bed with someone, trying to perform like a porn star'

A model shows off the Dean Street clinic's hotel-style waiting room

I walk into the clinic and it's assembled more like a hotel, with leather chairs and funky interior cultivating its setting.

David Stuart, the curator of the Wellbeing Programme, said this was the intention in a bid to get more people to visit the clinic.

He said: "We're seeing increases in the number of people having a high number of sexual partners in relation to apps.

"So nurses were seeing changes in technology and how it was affecting people's sex lives.

"You might find yourself in bed with someone, trying to perform like a porn star or a hero like you portrayed yourself to be (on an app).

"And that might translate to an unsatisfactory experience. It might even translate to you not communicating your boundaries to what you will and won't do with regard to your sexual health."

Mr Stuart, who also acts as lead in 56 Dean Street's chemsex (sex under the influence of drugs) clinic, said apps were continuously coming up in conversation between volunteers, nurses and clients pre-2014, prompting them to set up the service.

'An explosion of HIV in the heterosexual population'

56 Dean Street is said to be Britain's only sexual health clinic offering support for app users

In November last year the British Association for Sexual Health and HIV (BASHH) warned that apps could "start an explosion of HIV in the heterosexual population".

BASHH media committee chair Dr Peter Greenhouse said: "You are able to turn over partners more quickly with a dating app and the quicker you change partners, the more likely you are to get infections.

"What really worries me is that we are just at a tipping point for HIV."

He referred to Public Health England data suggesting syphilis was up 33% and gonorrhoea was up 19% in 2014.

Quite why the use of dating apps may have caused an increase in STI's is obvious, Mr Stuart says, pointing to increased access to a larger population of sexual partners.

The use of GPS to find sexual partners is also resulting in 'cluster infections', he adds, where infections break out in a certain area because people are sleeping with each other in close proximity.

'Someone is selling a PR'd version of themselves'

At the Wellbeing Centre, clients can talk about what they want from their sex lives

But aside from treatment and prevention of STIs, the programme targets the problems that stem from creating an alter-ego online.

Mr Stuart said: "It became 'how can we support patients how to understand apps, how to write profiles in a way that reflected what they want and how they perceive themselves?'.

"Rather than just how they want to be perceived, how they perceive themselves. Because we use apps to sell ourselves.

"Imagine if you were looking for a date, or even if it was just more casual than that, you were just looking for someone to 'hook up' with tonight.

"Let's jump back to 1990 where it might have happened in a bar or on a date in a restaurant where you're face to face with someone.

"Facial expressions, that's how we intimate, that's how we communicate and you form bonds that way much easier.

"So now forward to 2016, trying to do the same thing without the facial expressions when we're communicating with an Avatar, someone is selling a PR'd version of themselves."

Mr Stuart said he would begin by asking them what they want from their sex and romantic life, either casual or something more, which can be "foreign concepts" to generation app.

Typically, the client may have collected STIs, connected to app use, and the team of volunteers, psychologists, councillors and drug workers all work to support them in addressing the needs that led to the infection.

What does your profile picture say about you?

Arrival at 56 Dean Street, situated in Soho

He added: "I like to think that sex, whether it's casual or not, does involve to some degree intimacy and a bit of trust and wanting the person to like you and wanting to like someone else.

"So if we start with your profile, what does your picture say? And what does another person interpret from that picture? Is it a photo-shopped picture of a torso, is that how you feel when you're in bed with somebody?

"Is that what you want someone to prioritise about you if they are going to hook up with you?

"It might say, I'm fit, I'm sorted and I want sex now. Which, okay, that doesn't tell me anything about you at all.

"Then we would explore that, some people do want an experience based on a torso and putting anxiety into that where they say I will be rejected unless I am perfect.

"There are many sexy things about you - say 20 - and only five of them are physical attributes, and 15 are about things I can't even see right now (on an app)."

I concluded our interview by asking Mr Stuart if apps were the biggest change to people's sex lives he had ever witnessed.

"Yes," he replied. "Perhaps probably in many, many generations."