Originally Posted by
dsquared37
But they have no idea where you are and you don't know what level they are on. What you've typically done will not bear fruit in BKK.
I've received calls from Uber drivers in Paris and Bangkok to my US number. While it's possible that they may have had plans on their phones allowing them to call internationally I think the most likely scenario is that they have a way to call you via the driver uber app with the call being routed like a VOIP call i.e. free for them.