All. :rotfl::rotfl::rotfl::rotfl: but whatsapp (never liked it) and BBM (after 5 year of blackberry I hate anything BB related)
iMessage (rarely)
Viber (always, most used)
Wechat (sometimes)
Line (sometimes)
KakaoTalk (my favorite, sometimes)
Kik (rarely)
Threema (never, so far)
MyEnigma (very rarely)
Telegram (sometimes)
Surespot (never, so far).
Actually I am not using all of them simply because I do not have any contact using Threema, Kik and Surespot. All the others work fine with the exception of Telegram which is still a bit buggy: new contacts are not always syncronized.
Wow, that's a lot! To tell the truth, I've also registered with many IM apps, but seldom used any. I was trying to help our team reach out to our users but don't know how.
Ok, we've opened a Facebook Page and a twitter account, and even a skype account, but no one seems to be interested.
Maybe my next thread would be "how would you like to contact to a developer if you are using his/her app?"