Ever since it was reported that Apple is finally coming out with the iOS 9, many followers of the Cupertino-based firm are eager to see what's next in store for Apple devices.

Among the major things iOS 9 is expected to bring is an all-new design for Apple's voice assistant, Siri, reported 9to5Mac. Siri was first introduced in the iPhone 4s four years ago and has undergone minimal changes since then.

However, reports indicated that the upcoming Siri in iOS 9 could be the same as the one installed in the Apple Watch. Current versions of Siri only show a white line when it's in use but the smartwatch version shows a colorful line instead.

While this is not much of a difference, it is rumored that the color interface is just the beginning of numerous updates to come to the famous voice assistant.

Another thing to look forward to is the reported addition of the updated Music app that was first unveiled in the iOS 8.4, noted Ordoh. People first learned of the upcoming OS when a tech site leaked a photo of the iOS 9 Firmware being tested for the application.

Tech Radar wrote that with Apple's acquisition of Beats and Beats Music, it is possible that these would be integrated with the new operating system. No word has come out on whether the said music service would continue to carry the Beats name, or switch to Apple when it does.

For travelers, this other rumor could be very helpful during trips overseas. It has been reported the Tim Cook-led firm is set to update the existing Apple Maps to include available public transportation options in an area.

It was initially rumored this public transit upgrade would be found in the iOS 8. However, it did not see the light of day when the OS was unveiled in 2014. This feature would show users directions to the nearest mode of public transportation available.

For users who want quick access to most of the phone's applications and features, developers are reportedly looking to add more navigation options to make things easier.

While iOS 8 already made significant improvements in this area, some people believe that more work could be done to easily switch on Bluetooth and Wi-Fi menus.

The iOS 9 is rumored to make its first appearance on June 8 at the WWDC 2015 event