I'm not so sure that the "walled garden" idea is enough to protect your IOS device. I would agree that Android has a much bigger problem because of the known presence of malware within their app store, but your Apple IOS device is still connecting to the Internet. And IOS, like any other operating system, will have vulnerabilities - I think it's a matter of time before exploits become fairly common. The target must be very attractive to online criminal types as so many users are currently running without any kind of protection, and they use their smartphones for EVERYTHING!

Having said that, this particular app seems to be somewhat underwhelming. If it only scans what the user specifies, and when the user specifies, then I think most malware will slip through without any difficulty at all. Relying on the user to understand what should be scanned without offering any other kind of protection? Not good enough in my opinion. In this case the low price is probably a good indication of the level of protection being offered.