1-It pick default primary email of your phone for receiving missed call alert notification.You may edit to it to forward on any email.
2-If Wifi is on then all missed call will be forwarded to your gmail account by default otherwise email chosen by you.
3-If you have forget your phone and wifi or data is not enabled and your app is on,do not need to worry it automatically enabled data for some seconds and then automatically disabled to it.
4-if caller phone number exits in your contact then it will mention in it other wise unknown caller mentioned in forwarded email.
Criteria Required for this app:
Only Gmail account required for login this app.Access for less secure apps should be enabled is your gmail.
if this not happen then a email will forwarded to login account on first missed call.