3.50€ for an IM app when there are dozens that are free? Yeah, no.
I'd respect Telegram more if I had to pay for it from the start.
3.50€? Seriously, people use more on coffee.
"Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety." - Benjamin Franklin
Seriously, at least for westerners, if we cannot pay the same for a secure messaging app as for a coffee then we don't deserve secure messaging.
(That said, I'm in no position to say if this IM app is good or bad, just reflecting on the general idea.)
plus I don't really spend money on unnecessary things or pleasures, at least not regularly as your typical daily coffee drinker