CCLS Mobile provides you with library information on the go! Check your account, find and request books, movies, and music with direct access to our catalog. Connect to OverDrive to download e-books and e –audiobooks to your mobile device. Research is made convenient with CCLS Mobile. The app contains some of Chester County Library System’s most popular databases, such as Mango Languages, Learning Express Library, and ReferenceUSA. Stay connected with local libraries, their locations, hours, event calendars, social media pages and more.