The man killed her by strangling her with her 'dupatta'.
According to reports, the man was also pressured to return a loan he had taken from the woman.
As per the police, the man alleged that the woman, who was a mother of four children, also allegedly used an Instagram filter to make her look younger, which irked him, too.
Mainpuri Superintendent of Police Arun Kumar Singh said on Tuesday that the police found an unidentified woman's body near Karpari village in the district on August 11.
Strangulation marks on her neck indicated she had been murdered. Later, an autopsy was conducted, which confirmed the strangulation.
After checking with several police stations in the state, they identified the woman as a resident of Farrukhabad, based on a missing persons complaint.
The accused, Arun Rajput, was taken in for questioning by the police.
He told them he had become acquainted with the woman on Instagram, and they had been friends for a year and a half.