Measuring inflation is not straight forward. How do you calculate inflation of completely new products, like smartphones? How do you measure inflation on a car

Measuring inflation is not straight forward. How do you calculate inflation of completely new products, like smartphones? How do you measure inflation on a car that is superior in every attribute (fuel economy, safety, reliability) to a car of 10 years ago? How do you measure inflation on non-rival goods, like access to wikipedia?