Hmm, my mailbox situation is getting out of control and it's not a nice place to be, esp. in a world where every other payment or ordering kiosk asks for email or phone number. When you go through email you are fighting for breathing room against so much other junk.

My intuition is that a bible app is something that's intimate and focused enough that people would be willing to visit a separate website or download a separate app for, and that being in separate places creates a good psychological boundary.