The proprietor of at least one third-party app store was found using a new method of subterfuge enabling the store to be legitimately placed inside Apple's official App Store.
Trend Micro found a case where a household financial helper app was available on the App Store, but instead of operating as its name would suggest it was actually a front for an illegal third-party app store.
If downloaded, the fake app will at first appear to be the accounting app that was advertised, but if left open it will eventually switch views showing the illegal third-party app store. The imposter app uses Japanese characters, but the app store itself is written in Mandarin Chinese.
The reason why anyone would bother to pull off this trick was a mystery to Trend Micro's researchers. Not only is extra effort needed to create a fake app that meets Apple's App Store criteria, but any third-party apps downloaded by the victim have to use a roundabout process to be installed.
This particular fake app has been removed by Apple, but while it was functioning, one app it was distributing was a jailbreak app that had been previously banned by Apple. Trend also noted an illegal app store can be used to distribute malware in what would otherwise be considered a safe environment.