Explain the purpose first
GPS check-in confirms that a visit happened at the customer's location. Say that clearly, and say what it isn't used for.
Show exactly what's recorded
Walk the team through a visit record: check-in time, distance to the customer and GPS accuracy. Show the consent prompt they'll see on their phone.
Agree how exceptions are handled
Weak GPS, a customer who moved, a meeting at a different branch — decide in advance how these are recorded and reviewed, so a flag is a conversation, not an accusation.