There are actually dozens of these apps for iOS (and have been around for years) including Manga Rock and Manga Storm. There's actually a tweet from Zac Bertsc

There are actually dozens of these apps for iOS (and have been around for years) including Manga Rock and Manga Storm. There's actually a tweet from Zac Bertschy, Executive Editor of Anime News Network that complained about how many are available on iTunes: https://twitter.com/ANNZac/status/202096701534765056 https://twitter.com/ANNZac/status/202096701534765056