Using your phone (or mobile device), go to your App Store or equivalent. Search for “Instant Church Directory” (looks like this). Load that app.
When you load the app, or when you first start it, you will register. Your username is your email address on file with church. It might just ask for your email address, but that is the username as well.
This email address is already in your profile. When you register, the service will send you a password to your email. So open your email, copy the password, and paste that into the app. From there the app just works when you start it on your phone/mobile device.
Caution: If you decide to use the website version, and choose to reset the password, you will have to remove and reload the app on your phone, and then re-register. So, don’t do that. Otherwise, it is a pretty simple app on the phone.