Apple iCloud is an online storage and syncing service for a wide range of data, including music, emails, photos, files, contacts, calendars and software. iCloud also offers iOS device backup and is able to integrate directly with third-party apps. Unveiled in June 2011, iCloud is the fourth generation of online services provided by Apple. It replaces MobileMe, .Mac and iTools.
In September 2014, Apple’s iCloud service came under scrutiny after intimate images of celebrities were stolen and leaked to the public. Experts warn that iCloud’s security measure, called two-step verification, can be bypassed using easily available software.