WhatsApp has been working on the feature for about six months, wanting to make voice messaging simpler and easier to use than other apps with the functionality, CEO Jan Koum told AllThingsD in an interview.
Other perks of the new voice messaging feature include no length limit on recorded messages and volume controls that automatically adjust based on ambient influences. For example, when listening to a voice message, the volume will fluctuate based on how close a device is to the user's ear. In addition, a blue microphone illustration notifies the sender when a voice message has been heard.With the updated WhatsApp, a user pushes to record a message rather than type one. When she lets go, the message sends. If she decides not to send, she swipes to the left and the recording is deleted. All that is built into a single tap.
Article Link: Popular Messaging App WhatsApp Adding One-Tap Voice Messaging