How close does pin pad need to be to Smart Lock?

My wife doesn't like the look of the pin pad on the door as she doesn't like having three different things on the outside of the door (a door handle, a deadbolt key, and then the Simplisafe pin pad).

How close does the pin pad have to be to the smart lock for it to work (once they're already paired)? Wondering if there's a discrete place outside I can place the pin pad rather than on the door directly above the deadbolt lock.