Security firm Zscaler has lifted the lid on a porn app - that was holding its users' data hostage.
According to the BBC Adult Player, which wasn't available from a vetted store front and thus had to be downloaded from a specific website, appeared to offer porn but...
The app actually secretly took pictures of its users, and then locked their devices with a demand for $500 (about R7,000).
Ransomware, malicious software that threatens to either delete your data or release it to others, is a growing menace.
"Apps like this rely on the embarrassment factor. If you don't pay, your reputation is on the line," Raj Samani, chief technology officer for Intel Security in Europe told the BBC.
Most of it affects desktops and laptops - where incidents have increased by 127% since 2014.
"There are people you can pay to do the work for you, and it pays really well. One group we tracked made more than $75,000 in 10 weeks," Samanji said.