In the updated version of Viber, your last online status, and your friends' status is displayed. To show or hide online status on Viber for Android, follow these steps:
1. Open "Viber"
2. Hit the Menu Button and select "More Options"
3. Tap "Settings"
4. Scroll down and find "Display My Online Status"
5. If it is unmarked, then the online status of you and your friends is hidden
** Note that, this option can be modified every 24 hours