Mobile app cloning from unauthorised app sites now affects 97 percent of the top 100 paid Android apps and 87 percent of the Apple iOS apps in the same category, with financial services, healthcare and retail popular targets for criminals, Arxan Technology's annual survey of the phenomenon has found.
For the top 20 free apps on the two platforms, the percentages are almost as bad at 80 percent and 75 percent respectively.
Incredibly, for Android at least, this is a slight improvement over last year when the top 100 paid app-cloning percentage was 100 percent although Apple's has deteriorated markedly from the 56 percent found then.
The main sources of these apps are the dark side of third-party sites and Torrent downloads so this is an issue that would only affect foolhardy Android users and Apple users with jailbroken devices.
Unexpectedly, among these apps are many financial, healthcare and retail apps one might assume users would only download for free from the official app stores or the providers themselves.
Looking at the top 40 in each category, Arxan found that the cloning of financial apps has reached 96 percent on Android and 70 percent on iOS, both increases compared to 2013. For retail, the figures was 90 percent for Android and 35 percent for iOS while for healthcare it was 90 percent for Android (the Apple percentage was not quoted).
For the average user who sticks to the official app store, none of this will be of much concern which suggests that it is the app developers themselves who have most to lose from an app cloning industry that is essentially borrowing their brands to spread malware.
"It's evident from our research and various reports from leading industry experts that mobile applications are vulnerable to reverse-engineering, repackaging, republishing and susceptible to becoming malicious weapons," said Arxan.
"To combat these threats, organisations must adopt pre-emptive and reactive measures," it said, including runtime protection and code confidentiality.
More serious, of course, is the possibility of direct assault - the Masque and Wirelurker attacks have hit the assumed invulnerability of iOS platform hard in recent weeks.