Recs.
Updated
SpecsUpdate
Pros
Pro Insight and well documented encryption
Viber has made a documentation available, explaining in great details their encryption system and giving good insight on how it works.
Pro Desktop apps allow texting, calling and enables transferring calls between devices
Viber has native apps for both Windows and Mac that allow you to send and receive messages from your desktop. You can also use the desktop to make and receive calls. Synchronizes between all devices you are using Viber on. Allows transferring calls between devices.
Cons
Con Aug. 2021 viber no longer allows multiple devices
For years I had viber on a tablet and my phone. Got new phone but have not activated it yet. Just installing apps and getting it ready. Installed viber on new device now I am constantly having to setup viber on tablet which causes viber to not work on new phone. Then if I want to use viber on new phone have to get new code and then viber on tablet does not work any more. Totally sucks since I always leave my main phone in country and only take tablet abroad mainly to use viber to call back into country when I have bank issues. It used to work perfectly WHY DID IT CHANGE?? Will start looking for replacement I think!