It has often been questioned if it is necessary to switch your phone to airplane mode while on an airplane. Does leaving your cellular data on send radio wave interferences that hinder the flight?

In short it is doing the flight crew a disservice if you choose not to switch your phone to airplane mode. It can interfere with the radio communications that are necessary for the flight crew to do their job and get you to your destination safely.

As for battery life it has been proven that putting your phone on airplane mode does increase the overall battery length and health. The reason it makes a difference is because when the phone is on cellular data it is doing a lot more because a lot of services use cellular data and can run in the background of the phone meaning that the battery can be constantly losing battery health.

In the article What Does Airplane Mode Do? And Can It Save Battery Life? it does go over this subjects more in depth. Click on the link below to get to the article.