I started using the Starbucks app this month. So far, the major consequence has been that I spend a lot more money on Starbucks, even when I don't want to. It's good for Starbucks and bad for me — or any consumer who uses the app to order their drinks before setting foot in one of the chain's stores.
One technique I’ve used to help cut down on coffee is to stop using the Starbucks app. If I do want one, I have to pay full price for it.