Telegram isn't secure. There's been no public audit of their "secure" code and most messages aren't even sent via the secure channel unless you expressly tell it to do so.
It has a pretty UI though, so most people seem to think it's great.
Their UI is a carbon copy of WhatsApp
This.
Why do you require Google Play services?
Why do you spy on contacts?
It's explained here: http://support.whispersystems.org/customer/portal/articles/1...
I hadn't herd of their new app Signal. Has anyone tried it? I'm really interested in hearing anyone's experience using it.
BTW, I ended up installing Telegram ...and it may be mere co-incidence, but I started noticing some weird things happening that I've never seen before. I connect to the internet exclusively via tethering to my phone and while tethered I started seeing messages in Firefox from my desktop machine giving warnings that were something like "Could not establish secure connection because the server supports a higher version of TLS". My guess is that it was some sort of MITM attack... and I was possibly targeted due to the traffic to Telegram servers.
One other thing regarding Telegram: I really don't like that it reads my contact list and uploads it to their server to check if my contacts have a Telegram account. I've blocked the permission for now.