Why do iphones need Wi-Fi for functions when they have cellular data?

Why do iphones need Wi-Fi for functions when they have cellular data? - 1

Because Wi-Fi is faster, cheaper and often more reliable than a cell connection, so it's recommended (or even required) for certain functions.

It's cheaper for the wireless carriers-data is the most expensive function to run, update, and maintain on a cell phone tower. To put the Wi-Fi function on a phone and encourage you to use it saves them money so they can lower there rate plans