A single mother has admitted using a smartphone dating app to pimp out a teenager for group sex.

Monika Kelly, 19, created a profile for a 14-year-old girl on Seeking Arrangement, an app for 'sugar babies' and 'sugar daddies'.

After changing the girl's date of birth to make her appear 18 or 19, Kelly then arranged for her to meet men for sex at two Auckland hotels and an office building.

Monika Kelly, 19, created a profile for a 14-year-old girl on Seeking Arrangement, an app for 'sugar babies' and 'sugar daddies' (pictured is the app)

In March 2017 the victim was taken to an office building where she had sexual intercourse with a man and gave him an oil massage, Stuff.co.nz reported.

Kelly was paid by the man, and she gave a share of the money to the victim.

Two weeks later, Kelly arranged for the victim to have group sex with the same man and his associates at Auckland's City Life Hotel, charging $350 for 90 minutes.

Despite the arrangement for group sex only one man showed up, court documents stated.

A single mother has admitted using a smartphone dating app to pimp out a teenager for group sex (stock image)

The 19-year-old pleaded guilty for one charge of sexual exploitation of a minor at the High Court (pictured) at Auckland on Friday

A week later the victim was taken to the Best Western President Hotel to be filmed having sex with a man for $200.

Kelly then took the victim back to City Life Hotel to have sex with a man for $350 on ANZAC Day, while she waited outside.

Throughout all the incidents of exploitation, Kelly was given the promised payment for every arrangement and gave part of the payment to the victim for one arrangement.

When a police investigation began in July 2017, Kelly tried to prevent witnesses from providing evidence, court documents stated.

Kelly claimed she did not make the arrangements and was only trying to help the victim out, but pleaded guilty to one charge of sexual exploitation of a minor at the High Court at Auckland on Friday.

Justice Matthew Downs said Kelly would be sentenced on 13 November.