Android M, the next version of Google's mobile operating system that will be launching this fall, will feature built-in visual voicemail support for its dialer function.

Native support for visual voicemail would mean that there will no longer be a need for all carriers to develop their own apps for the feature. However, the catch is that each carrier will be required to add support to their services for the visual voicemail service that will be included in Android M, and it seems that most carriers will not do so just yet.

T-Mobile and Orange, a French carrier, are the only carriers onboard with Android M's visual voicemail feature, which would limit the number of Android users who will be able to enjoy the upcoming feature to the subscribers of these two networks.

Visual voicemail support for T-Mobile and Orange subscribers should immediately be available once Android M is released, with the feature already present in the developer preview of the operating system.

Visual voicemail has been a feature that has been sorely missing in Android smartphones, especially since the feature has been in the iPhone since the first version of the device was launched back in 2007.

Android-powered smartphone users had to resort to the individual apps of carriers or on services such as Google Voice to have such a feature on their devices. There are some carriers that are charging extra for the feature, which could be the reason why some carriers would want their subscribers to keep using their visual voicemail app as opposed to the one to be included by Google in Android M.

Apple, meanwhile, worked together with AT&T to be able to release the visual voicemail feature to almost all users.

The addition of the visual voicemail feature was discovered in a support ticket for the developer preview of Android M that was first spotted by Android news website Android Police.

According to the ticket, the "basic implementation" of the feature is already included in the developer preview, and that visual voicemail will be available once Android M is released in the fall.

Native support for voicemail transcriptions has also been added, but the feature will only be activated if carriers decide to provide the service, which no carrier is so far doing.

While the discovered support ticket is not an official confirmation, it is a good enough indication that visual voicemail will be coming to the Android M.

Android Police was also able to capture a screenshot of what could be the feature in action, as posted by Google+ user Danny Hollis in the community page for the Nexus 6.