For some experiences, such as turn-by-turn navigation or local search, location is the central feature, but increasingly, new types of applications in music, sports, and entertainment are incorporating location to personalize content delivery.
This monthly enrollment feature is in contrast to the other types of pre-tax benefits, like health care flexible spending accounts, which limit your ability to sign-up to just once a year during open enrollment period or when you experience a qualifying life event, such as the birth of a child.
It's entirely arbitrary to treat differential rates for different levels of income as a structural feature of the tax code but differential rates for different types of income as a tax expenditure.