iCloud is described as 'Store email, contacts, calendars, photos, music, books, apps and more in the cloud and access them on all your devices. iCloud also provides collaborative services for task management and notes and productivity apps for text documents, spreadsheets and presentations' and is a very popular Cloud Storage service in the backup & sync category. There are more than 100 alternatives to iCloud for a variety of platforms, including Web-based, iPhone, Windows, Mac and Android apps. The best iCloud alternative is Dropbox, which is free. Other great apps like iCloud are Nextcloud, Google Drive, MEGA and Proton Drive.