WhatsApp is not free to use. iOS users are charged a flat 99c fee while Android users are charged 1$ a year from the second year onwards.
I do not know how secure Viber is but they have been steadilu acquiring good user base. If I was Viber, I would cash on this opportunity to write a blog or advertise their security models.
I do not know how secure Viber is but they have been steadilu acquiring good user base. If I was Viber, I would cash on this opportunity to write a blog or advertise their security models.