You pay for a latte with money from your Starbucks app, so your bank account balance doesn’t change. That means the coffee was basically free, right? This is just one example of “girl math,” a trend ...

This may be a girl’s girl summer, but buying tickets for Taylor Swift’s Eras Tour, dressing up for Beyoncé’s Renaissance Tour, and going to see the Barbie movie isn’t cheap. This is when every girl’s ...