A US man has been handed a US$500,000 fine for selling the StealthGenie malware in the first prosecution of a mobile spyware slinger.

Police collared Hammad Akbar, 31, in September after he allegedly sold the malware to an undercover agent in 2012.

Akbar a Danish citizen, sold the StealthGenie malware capable of intercepting calls, text and media and tracking location on Apple, Android and Blackberry phones to more than 100,000 'customers', according to a YouTube promotional video.

FBI assistant director in charge Andrew McCabe said in a statement Akbar was the first person to cop to selling spyware.

"This illegal spyware provides individuals with an option to track a person's every move without their knowledge," McCabe said. "As technology evolves, the FBI will continue to evolve to protect consumers from those who sell illegal spyware."

Akbar was sentenced to time served, fined half a million dollars and ordered to hand over the StealthGenie source code.

The app appeared to attempt to root Android phones and was detected by at least some anti-virus apps.

StealthGenie required access to a victim's phone in order to install the application and run it as a background service. ®