Google has finally added offline support to Gmail, allowing US and Blighty-based users to read and write email while unconnected to the interwebs.

The firm said it was rolling out an “experimental feature in Gmail Labs” that will probably be a bit cranky and frustrating due to the fact that there are still “some kinks that haven't been completely ironed out yet”.

Gmail engineer Andy Palay said in a post on the company’s offical blog yesterday that Google has been testing the offline version of Gmail for some time.

Indeed many have been patiently waiting for the manacles to come off of Gmail, because up to now it was limited by the fact that messages could only be accessed online.

Of course, Gmailers wanting offline access could simply opt for a separate POP client such as Thunderbird, Apple Mail, or even Microsoft's very own Outlook.

Google entered the offline web app market in May 2007 with the release of its browser add-on project Gears.

At the time the firm marked out clear intentions to enter territory dominated by Microsoft by offering free, open source apps such as docs and spreadsheets that work without an internet connection.

However, it’s taken Google over 18 months to include email in its Gears project. In that time the company has suffered several major outages in Gmail that have perhaps best illustrated the limitations of storing users data up in the cloud.

The offline version of Gmail now uses Google Gears, which downloads a local cache of an individual’s mail and synchs with Mountain View servers when connected to its network. A fact that could prove a storage headache for some.

The feature has to be switched on via Google’s email testbed environment Gmail Labs. It will be made gradually available to individual Gmail account holders as well as Google Apps biz customers in the US and UK over the next few days.

Oh, and an offline option for Google Calendar will be winging its way into Gears soon too. ®