Telegram app (telegram.org) is apparently is safer and more open than WhatsApp. If we really care about open communication such important infrastructure should really not be a service but more of a protocol. It should never be worth as much as Facebook paid for it.
Telegram is a centralized service. Also, consider this <a href="http://www.cryptofails.com/post/70546720222/telegrams-cryptanalysis-contest" rel="nofollow">http://www.cryptofails.com/post/70546720222/telegrams-crypta...</a>
Disclaimer : I'm neither of Whatsapp not Telegram (I resisted being on FB for longest time, even now - I occasionally visit FB)<p>I think importance of "Social Networks" is based on the user base.
So while security is important - if you are the only person on such social network, what does it matter ? You can't "share stuff" cause there aren't enough people there.
So moving to telegram makes sense only when enough of "your friends/family/relatives" are there.