San Francisco: Shady apps have reached Apple Mac computers using pop-ups, and seamsters are making it difficult for Mac users to quit an app without paying outrageous subscription prices. According to The Verge, scammy apps have made their way through the App Store, without Apple noticing, despite a stringent App Review process in place to keep users safe from bad apps. Scam app hunter and developer Kosta Eleftheriou saw one such app called 'My Metronome' that locks up and won't let users quit it until you agree to a $9.99 per month subscription. "This App Store app immediately asks you for money and then disables the 'Quit' option so that you can never close it! And it's been like that on the App Store for years!," Eleftheriou tweeted. "This app literally locks your machine until you pay the fee. It is almost ransomware. No way to report it," tweeted Edoardo Vacchi who first discovered the app. Also ReadNew iPad Air to upskill creators, gamers, students in ‘hybrid normal’ The 'My Metronome' has now been removed from the App Store. Another developer Jeff Johnson discovered that the firm behind My metronome app called Music Paradise is connected to another App Store developer, Groove Vibes. "The privacy policies listed on both developers' websites say they're registered at the same address, and both mention the same legal entity, Akadem GmbH," the report noted. "Apple has let plenty of other scammy apps that flagrantly break its rules slip through the cracks," it added. Third-party apps have grown from 500 to more than 1.8 million since the App Store's launch more than a decade ago, and a new report has found that third-party apps experience broad regional and global success on the App Store, even eclipsing Apple's own apps. According to Apple, which offers 60 first-party apps, more than 99.99 per cent of iOS apps are made by third-party developers. According to economists at Analysis Group, third-party apps are the most popular among iPhone users in most regions for major app types, including music streaming, TV and movie streaming, reading, communication, and mapping apps.