As announced last week, Apple (NASDAQ:AAPL) is expected to release the iOS 7, the revamped version of the company’s mobile operating system, on Wednesday.

The iOS 7, which is lauded as the biggest update to the platform since the launch of the original iPhone in 2007, will have an all-new design and user interface and will bring many new features, such as Control Center, photo filters, AirDrop sharing and iTunes Radio.

Although Apple will roll out the iOS 7 on Wednesday, the company has not revealed the exact release timing of the new firmware. However, if Apple follows its conventional release time for major iOS versions, including the iOS 6, it is very likely that the iOS 7 will be rolled out to the public at 10:00 a.m. PDT (1:00 p.m. EDT) in the United States, Redmond Pie reported.

Here are the expected release timings for the iOS 7 in some of the key cities around the world:

London - Wednesday 6:00 p.m.

New Delhi - Wednesday 10:30 p.m.

New York - Wednesday 1:00 p.m.

San Francisco - Wednesday 10:00 a.m.

Shanghai - Thursday 1:00 a.m.

Tokyo - Thursday 2:00 a.m.

Melbourne - Thursday 3:00 a.m.

Auckland - Thursday 5:00 a.m.

For details on iOS 7 release times for more countries, click here.

Users should also note that Apple may not release the iOS 7 update simultaneously around the world as it could trigger server overloads and instead, stagger its release based on different time zones.

And now that the much-awaited update is around the corner, the first thing that users should do while preparing for the update is to get familiar with the list of devices that will be compatible with the iOS 7. Although the new OS will be available on many devices, not every device will support all the new features. For instance, AirDrop is compatible only with the iPhone 5, iPad 4, iPad mini, and iPod touch fifth generation.

Before updating to any new firmware, users should also perform a proper back up of their devices. Although highly unlikely, there are chances that updates could encounter errors while installing and, thereby, wipe out all the data. Users can back their devices up by syncing with iTunes, or through iCloud. Click here for more details.

Users are also recommended to download the latest version of iTunes. While the current version of iTunes is 11.0.5, an updated version -- most probably iTunes v11.1 -- is expected to be released alongside the iOS 7 on Wednesday. Users should ensure that they are using the latest version of iTunes available, before installing the new iOS.

Users who have decided to update their devices to the new iOS 7 should go through the apps currently installed on their devices and delete the unused ones. Before installing the iOS 7, users should also ensure that all remaining apps on their device are up-to-date.

Meanwhile, users of jailbroken devices must save their Signature HaSH blobs, or SHSH blobs, if they want to downgrade to an earlier version of the iOS in future. For a step-by-step guide on how to save SHSH blobs, click here.