樂天Kobo is an iPhone application developed by Kobo Inc. that provides users with access to over 4 million electronic books in various languages. The app offers a customizable reading experience, allowing users to adjust text size and style according to their preferences. It also includes a night mode feature for comfortable reading before bed. Furthermore, the app provides personalized recommendations based on users' reading habits, making it easier to discover new books.

The application allows users to pick up reading right where they left off, thanks to its automatic synchronization of bookmarks, notes, and highlights across all devices. Users can also share their favorite content, quotes, notes, and thoughts on Facebook, Twitter, and Instagram. The app also provides book ratings and user reviews to help users make informed decisions about their reading choices. Overall, 樂天Kobo is a great app for book lovers looking to access and discover new books in various languages.