Nearly 30 per cent of Brits say they've used a dating app despite being in a relationship, while more than half of those surveyed would dump their partner if they caught them seeking love online.

Law firm Slater and Gordon carried out the research on 2100 respondents in the UK after noticing a spike in the rate of dating apps usage being cited in divorce proceedings.

"Although a large number of people have admitted to using dating apps while in a relationship it's apparent it is not something we are all willing to accept as part and parcel of the modern-day dating life," Divorce lawyer Niamh McCarthy said.

"Previously these apps wouldn't have been involved in relationships but within the last two to three years we have seen a steady rise in them being referred to in divorce proceedings."

Of those surveyed some 30 per cent admitted using a dating app while in a relationship, with almost half of men (46 per cent) and just over one in five (21 per cent) women owned up to looking for romance behind their partner's back.

Among men, the top reasons for straying onto dating apps were boredom (10 per cent), a dwindling sex life (nine per cent) and lots of arguments (seven per cent).

Women said they used the tools because they were bored (four per cent, embroiled in arguments (four per cent) or were lacking attention (three per cent).

One in five of those surveyed said they "wouldn't mind" if their partner used a dating app, but half said they would expect their boyfriend or girlfriend to quit using the apps as soon as they became official.

Over half (53 per cent) of all those surveyed said they had been cheated on in the past, with 31 per cent finding out after discovering secret messages, a quarter learning of the betrayal from a friend, and one in five catching their cheating partner in the act.