Credit card stealing app in Apple's official store

The other day, I downloaded an update to an iPhone app that I own that streams Romanian radio stations called roRadio. They added a page of ads that are displayed each time you open the app, and they struck me as a very candid assessment of what tech-savvy Romanians are into. The first one (in no particular order – they're displayed randomly) is an ad for a DEX app. DEX is the official Romanian dictionary, and, for what's essentially a dictionary with some etymology notes, it comes up surprisingly often in everyday conversation with Romanians. The second is some utility with Romania-specific facts – not exactly sure what they are, but it seems pretty normal.

The third one, though, is the most fascinating: it's an app whose only apparent utility I can see is to credit card thieves! It's 99¢ and I didn't buy it, but according to screenshots, it tells you the card issuer and whether or not a given credit card number is valid – things that you'd only need to know if the card in question wasn't actually yours (who forgets whether their card is a Visa or Mastercard??). Romanians are prolific hackers, but given Apple's notoriously stringent App Store policies, I'm surprised this one made it through.