A Tasmanian father who used Snapchat and WhatsApp to coerce underage girls into sending sexually explicit images and videos will spend at least 15 months in jail.
From November 2019 to June 2020, Samuel Christopher Norris used the two mobile phone apps to groom four girls, who were aged from 14 to 16.
Two lived in Tasmania, one in NSW and the other in America.
One of the girls, aged 15 at the time, sent him a picture of her naked with the words "Daddy's Girl" and "15 today" written on her body.
The pair exchanged 4300 text and video messages over a fortnight in June, with Norris becoming jealous of her speaking to other boys.
Norris, 33, who was aware the girls were underage, used the name Mike on Snapchat and Santa Clause on WhatsApp and told them he was younger than his actual age.
He sent the girls sexually explicit images and videos of himself and coached them to do the same.
He was on Friday sentenced in Hobart Supreme Court to three years and three months' jail, although nine months was suspended.
Norris was granted a non-parole period of half the operational sentence.
Justice David Porter said Norris' actions were deliberate and purely for sexual gratification.
He said Norris' social media use had become "an obsession" by the time his offending started in November, with the coronavirus pandemic creating a situation where he had "more leisure time".
Justice Porter said one of the girls felt physically fearful of Norris and was now anxious and suspicious when approaching people in person and online.
Norris had earlier pleaded guilty to four counts of involving a child or young person under 18 in the production of child exploitation material.
He also pleaded guilty to four counts of grooming a child or young person with the intention of exposing them to indecent material and two counts of possessing child exploitation material.
Police uncovered more than 500 child exploitation images and 54 videos during a search of his home in June.
Justice Porter noted Norris had shown remorse and wanted to make "a better person of himself".