While the App Store has not been updated (at the time of writing) with the latest changelog for WhatsApp since version 2.21.30 arrived last month a report by WhatsApp feature tracker WABetaInfo shows version 2.21.40 brings only a couple of small tweaks to the messaging service. There is a new progress bar animation for voice messages. Once a voice message progress bar reaches the end, it jumps back to the start. The report points out that this animation is only available on iOS 13 and beyond.
This update also tweaks the read receipt system for voice messages. If WhatsApp users on iOS have disabled read receipts, a contact that sent a voice message will not be notified when the user listens to it. Read receipts can be disabled by going to WhatsApp Settings > Account > Privacy.
The report adds that this feature has not made its way to Android yet so it is unclear if WhatsApp will push it to Android as well or remove it from iOS in the next update.
In November, WhatsApp added the disappearing messages feature to iOS and Android that allows users to automatically erase a WhatsApp messages after a certain period of time – seven days to be exact. It has to be enabled for individual chats and can be done by going to the particular chat on Android, tapping the menu icon on the top right, selecting View contact, and turning on Disappearing messages. iOS users can open a chat, tap on the profile icon, scroll to Disappearing Messages and turn it on.