Samsung Galaxy Note 4 was unveiled last year of IFA trade fair and made it to the market one month later. However, since Google did not release Android 5.0 Lollipop operating system a few months later, Samsung had to put a previous version of the platform on its flagship smartphone.
Android 4.4.4 KitKat was the newest version of Google's mobile operating system in September, so it made sense for Samsung to launch the Galaxy Note 4 with this version.
Obviously, the South Korean company confirmed it would release an Android 5.0 Lollipop upgrade for Galaxy Note 4 sometime this year.
Even now, many Samsung Galaxy Note 4 owners already have the new version of Android installed on their devices, but there are still some who don't.
Nevertheless, the Android 5.0 Lollipop update for Galaxy Note 4 does not come with the latest version of TouchWiz user interface, which is now included in Galaxy S6.
The good news is the new TouchWiz UI that is now getting into users' hands via Samsung Galaxy S6 will be rolled out to Galaxy Note 4 as well.
Before getting too hyped about this possibility, keep in mind that the information comes from unconfirmed sources, so we recommend our readers to take it with a grain of salt.
According to YouMobile.org, Samsung plans to release another Android 5.1 Lollipop update for Galaxy Note 4, which will also include the new TouchWiz UI that's now available on the Galaxy S6.
The update is expected to arrive sometime in the second half of 2015, but an exact release date is not available yet.
In the same piece of news, the report also claims the first smartphones to receive the latest Android 5.1 Lollipop update will be Samsung Galaxy S6 and Galaxy S6 Edge.
Update: It looks like YouMobile.org is not a reliable source of information. SamMobile claims that, according to their source, Samsung is not working on Android 5.1 Lollipop update for any of its Galaxy smartphones.
This means that Samsung Galaxy Note 4 will not receive the new TouchWiz UX included on Galaxy S6, at least for the next couple of months.