Apple announced the iOS 8.1 update, and fleshed out details of the previously-announced WatchKit software development kit ahead of the availability of the Apple Watch early next year.

iOS 8.1, which will start to be rolled out on 20 October, is the first major update to iOS 8, which was released alongside the iPhone 6 and 6 Plus in September.

It adds support for payment service Apple Pay for the smartphones, and a public beta of the iCloud photo library, with which all photos can be stored in iCloud.

“One of our major goals with iOS 8.1 is to address the top sources of customer feedback,” said Craig Federighi, Apple’s senior VP of software engineering, adding that this includes bringing back the “beloved” camera roll.

The update comes after the botched release of iOS 8.0.1 which was designed to address an issue with the integration of the HealthKit SDK. However, the release left some iPhone 6 users without phone reception or the TouchID functionality, with the company quickly addressing the issue with iOS 8.0.2.

Federighi noted that there has been “an absolute flood of updates to the App Store with applications, improving their functionality via extensions”.

Extensions enable third-party apps to be integrated with iOS 8 systems so functionality can be shared across the device, for example the integration of alternative keyboards to the standard Apple version.

Uptake of the newly-introduced Swift programming language has also been positive, with many applications using it already, according to the Apple executive.

In addition, Apple’s enterprise partner IBM “has completely embraced Swift for their customer enterprise application”.

Federighi compared the uptake of iOS 8, which currently stands at nearly half of all iOS customers after four weeks of availability, with Android. The latest version of Google’s OS, KitKat, has penetration of 25 per cent of the Android user base after more than 300 days of availability.

Including iOS 7, Apple claims that 94 per cent of the iOS user base is using a version of the operating system that has been shipped in the past year. In contrast, Federighi said “the vast majority” of Android users are running a version that is more than two years old.

The company announced at the launch of the Apple Watch in September that it was working with a number of brands — including BMW, America Airlines and hotel chain Starwood — to develop apps for its first wearable device.

Apple CEO Tim Cook said WatchKit means “many other developers can join this party” with the rollout in November taking place “in time for our developers to really do some fantastic work before we begin shipping Apple Watch”.