Be able to access where I last used Waze. aka, "Where did I lose my phone?"
I'd love to be able to find out where I was last, according to Waze. Wherever it was, that's where my phone must have fallen out of my car.
This would be fantastic for times like this, when the lost phone is apparently out of battery and can't be located by standard methods.
How about it, Waze? You could charge a per-use fee for this service if you needed to cover the costs of providing it. It would likely attract many new users, encouraged to become Wazers after being regaled with tales of how Waze saved the day for their friend with a lost phone.

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HeatherVsrt commented
P.S. Wasn't Waze bought by Google? Then the history feature should be especially easy to implement. :-D