Now you can 'unread'; 'quick reply' from notification on WhatsApp (Android)

In addition to the previous updates, here are some notable new ones in the recently released WhatsApp apk (version 2.16.4 available for download from APKMirror)
  • When attaching a PDF, you can now tap "Browse other docs..." to pick a PDF from another source, like Google Drive or Microsoft OneDrive (Android 4.4+).
  • View PDFs you've sent and received by tapping Media from contact info or group info
  • You can now view starred messages for a given chat from contact info or group info
  • When clearing a chat, you can choose to keep your starred messages
  • The ability to quickly reply to a message without opening up the app and the entire conversation. The expanded notification now show s a Reply button that opens up WhatsApp's own overlay. The window that pops up shows the message's sender, text, and includes a couple of options to answer. There's a text box, a vertically aligned emoji panel, a voice message option, and buttons to close it (which dismisses the notification without sending an answer) and view it (which opens the full conversation in WhatsApp) 
  • When you tap the profile or group image of any conversation (single contact or group), you get an overlay window with a faster way to perform the actions of the long-tap menu in the app's title bar. For a single contact, you get: Archive, Delete, Mute/Unmute, Add chat shortcut, View contact, and Mark as read/unread. For a single group, you get: Archive, Leave group, Mute/unmute, Add chat shortcut, Group info, and Mark as read/unread. You can multiple select chats, regardless of their muted, read, or contact/group state. 
  • The grey Default wallpaper icon is replaced wit a new circle icon with a color reminiscent of WhatsApp's own shade of teal green. A fifth option has also been added: solid color. This opens up a list of different solid colors that you can preview and apply for a bit of an added personal touch to your conversations.
Tips via Android Police
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