Dating apps have become a normal part of life for millions of singletons.
Many people rely on apps such as Tinder and Plenty Of Fish to meet potential partners, simply by using a smartphone.
But as they have grown in popularity over the years, a number of grisly murders have been linked to the apps.
Killers around the world have used them to target their victims with the simple swipe of a screen.
Some have murdered ex-partners for meeting new lovers through the apps.
There is no suggestion any of the tech firms facilitate wrongdoing.
But as more of our lives switch to online and we rely on our phones for all kinds of functions, it looks like they will continue to be mentioned in criminal cases.
Tinder, Grindr and Plenty of Fish have all been approached for comment.
Here are six court cases which have been associated with the phenomenon…
The cannibal cop killer
Stefano Brizzi invited Metropolitan Police officer Gordon Semple back to his south London flat in 2016 after they met on Grindr.
He strangled him to death before chopping up his body and trying to dismember it in an acid-filled bath, after being inspired by the show Breaking Bad.
The former web developer, who was high on crystal meth, also tried to eat his flesh with chopsticks.
He was jailed for at least 24 years at the Old Bailey in December 2016, but later hanged himself in prison.
The jealous ex-girlfriend
Shop assistant Hasna Begum stabbed her ex-boyfriend Pietro Sanna to death 36 times after discovering he had met someone new on Tinder.
In the days before carrying out her murderous plan, she used fake Instagram profiles to send threatening messages to his date.
Wearing a blonde wig and gloves, she went to the Italian part-time DJ’s home in Canning Town, east London in June 2017 – five months after they split up – and fatally attacked him.
She was later jailed for at least 20 years after being convicted of murder.
The Plenty of Fish killer
Carl Langdell met young teacher Katie Locke on the Plenty of Fish website and lied about being a lawyer.
He strangled the 23-year-old to death in a hotel room in Waltham Cross, Hertfordshire after their first date on Christmas Eve 2015.
The killer then dumped her body in a duvet near a skip.
Langdell, who at the time was serving a suspended sentence for threatening to kill a community psychiatric nurse, was jailed for murder for 26 years in 2016.
The liar who went looking for other women after killing.
The controlling killer
Anthony Lowe started a relationship with 26-year-old mum Katherine Smith on Plenty of Fish after faking his identity and pretending to be 10 years younger.
Two months later, in September 2017, “jealous and controlling” Lowe stabbed her to death 33 times in Cardiff after a row.
He started prowling Facebook trying to contact other women straight away.
After one said she thought he was in a relationship, he replied: “No, I am single now.”
He admitted murder and was jailed for 18 years.
The twisted ex-husband
Bitter Alexander Villaluna brutally stabbed his ex-wife Jovi Pilapil while she was having dinner with her Tinder date Keith Collins.
He approached her date from behind and asked, “what are you doing with my wife?”, before killing him in March 2016.
The knifeman then turned to his ex-wife, a nurse, and attacked her until she fled the restaurant in Sydney, Australia.
He was locked up for at least 30 years after admitting murder and wounding with intent.
The backpacker murder
British backpacker Grace Millane met her murderer through Tinder while she was travelling in New Zealand.
She went on a date with Jesse Kempson on December 1 2018 in Auckland.
The 22-year-old holidaymaker, from Essex, was later strangled to death in his hotel room.
He packed her body into a suitcase and buried her in bushland outside of the city, which was discovered eight days after she died.
The killer was convicted of murder and jailed for 17 years.