The accused, identified as Neeraj Bishnoi (20), has been arrested by the Delhi Police Special Cell's IFSO team.
"Neeraj Bishnoi, arrested from Assam by Delhi Police Special Cell's IFSO team, is the main conspirator and creator of 'Bulli Bai' on GitHub, and the main Twitter account holder of the app," Delhi DCP (IFSO) KPS Malhotra informed.
Bishnoi is currently being brought to Delhi for further legal proceedings, he added.
A resident of Digambar area in Assam's Jorhat, Bishnoi is a B-Tech student at Vellore Institute of Technology in Bhopal.
In the 'Bulli Bai' app, photos of hundreds of Muslim women were uploaded, following which many took to social media to complain to the police.
A journalist, who is one of the women named in the app, claimed that a group called "Bulli Bai" was created like "Sulli Deals" on GitHub, which would collect photos of Muslim women from their social media accounts and encourage people to participate in their 'auction'.
This is the fourth arrest in the case, the other three being done by Mumbai Police. Both Delhi Police and Mumbai Police had registered separate cases.
Earlier, three youths – an engineering student in Bengaluru and hailing from Bihar, a 18-year-old.
