In 2003 Apple released the first version of Safari, using a fork of the KHTML rendering engine they called WebKit. Safari became the default browser of the OS X series and the rendering engine has been adopted by a wide range of browsers since then, most notably Google Chrome uses a WebKit fork called Blink.

Today WebKit based browsers are dominating both the Mobile and Desktop markets, but in later years, the AppleWebKit development has slowed down a bit, and still more browser producers are switching to the Blink fork.

The Desktop Browser

The AppleWebKit rendering engine is used by a wide range of browsers, which can be considered as Safari - among others: iCab, Bolt, Iris, Iron, etc. Chrome is based on a WebKit fork called Blink and no longer identical to Apples WebKit fork.

In reality version detection is based on WebKit version, rather than Safari version. Some versions were released as security updates for older versions of OS X, but with updated WebKit versions. Thus Safari 5.1 is perceived as Safari 6 and Safari 6.1 as Safari 7, because that is what you'll find under the hood.

Versions 1 to 9

Based on WebKit 48 to 601 the early versions most notably lack support for FileReader, FormData and PushState.

These versions were released from 2003 to 2016.

Categorized as: desktop_light

Versions 10+

Based on WebKit 602+ supporting all current desktop requirements.

These versions were released from 2016.

Categorized as: desktop

The Mobile Browser

The iOS version of Safari is based on a slightly different WebKit and in all cases based on the iOS WebKit version, despite the  Safari version number (which primarily indicates the UI version). Certain features have been delayed in the mobile branch of Safari.

Versions 1 to 9

Version 1-9 is based on WebKit 419 to 601, and the early versions most notably lack support for FileReader, FormData and PushState. 

These versions were released with iOS 1-9 from 2007 to 2015.

Categorized as: mobile

Versions 10+

Versions 10+ is based on WebKit 602+ and fully support the smartphone segment requirements.

These versions were released with iOS 10+ from 2016.

Categorized as: smartphone

The Tablet Browser

The iOS version of Safari is based on a slightly different WebKit and in all cases based on the iOS WebKit version, despite the  Safari version number (which primarily indicates the UI version). Certain features have been delayed in the mobile branch of Safari. The iPad was released with iOS 3.2, which then also changed name from iPhone 0S to iOS.

Versions 4 to 9

Version 4-9 is based on WebKit 48 to 601, and the early version most notably lack support for filereader API and WebGL. They are also known to have serious problems with fixed-position element – but the scrolling looks great.

These versions were released with iOS 3 to 9 from 2010 to 2015.

Categorized as: tablet_light

Versions 10+

Versions 10+ is based on WebKit 602+ and supports the full tablet segment specification.

These versions were released with iOS 10+ from 2016.

Categorized as: tablet