ZIP files, as you'll likely be aware, are single archives of multiple files. Not only does a ZIP file condense the mess of several files into one manageable package, but it also helps to reduce the total file size. WhatsApp already supports a number of document extensions, though ZIP support should make life a tad easier for those with lots of files to send.
At a time when instant messaging has largely replaced real-time voice calling, the days of sending and receiving voicemail seem long gone. Even though users can already drop a voice note to their WhatsApp contacts on-the-fly, a forthcoming update will apparently add voicemail functionality. Details are scarce for now, so we're not exactly sure what this will entail. But presumably, it'll offer something in addition to what's already covered by the basic voice memos.
Finally, a call-back feature will let users quickly return a missed call without having to open Whatsapp—the option will likely be baked directly into the notification.
There's no word on precisely when these features will arrive, though each should hit Android and iOS devices in a forthcoming update.
source: Phone Radar