I just made the mistake of using swapy.app to do a crypto exchange.
Half a day later, and no response from customer support, and my money still hasn't arrived.
I can't say yet whether swapy is scam, but I can say this: Don't use swapy, it's crap. You could easily end up getting your transaction stuck if my first experience with them is anything to go by.
I really hope their customer support will give me my money back, but it's been a hassle at the very least... Use a proper crypto exchange.