This is a good communicating app in that regard however it annoyingly lets the unknown groups add you to their list and this takes over whatever you are doing at that moment. So sometimes you completely lose what you typed in other apps or all you edited in photo editors when the adding group attacks in telegram. I tried all trucks and setting to avoid this but impossible so far. Probably you need to remove all your contacts one by one to find which one leaks your information. That is a psin now with telegram.
February 19 2017