I STRONGLY advise against downloading something like Samsung Pay off an non-sanctioned APK. This is your credit card information you're talking about.
So not only are you taking the risk of keeping a phone that has already been recalled and given all the accommodations in the world to get it replaced or refunded, but you're gonna risk having your financial information up for grabs? To each their own, but be smart about this.
And on that Note (no pun intended

), a small reminder of how the Note 7 is just not worth keeping:
1) Recalled battery-related product, now a Federal Crime to bring on public transport and has to be clearly marked as hazardous material (and pay the accompanying premium) is shipped via courier. And airports are actively looking for it. I just got back from Hong Kong and one was detected on the X-Ray machine before going into the airport.
2) 60% battery limit update.
3) Most likely carriers will stop allowing the device to connect to their networks for other than emergency calls.
4) No more official updates or support from Samsung for the OS or any app on the Note 7. Soon they'll also block the model from working.
5) Insurance companies can legally void your home/renters insurance if you have a Note 7 in your home (it's already automatically void in the New Zealand, I believe).
6) Butt of every joke if your friends see the Note 7 out. Bombs away.