Supercharging Cost

While you're actively charging your vehicle at a Supercharger, the Tesla app will now display your current cost in real-time.
This is in addition the current power in kW, miles or km charging per hour and total energy added during the session that was already displayed in the app.
Supercharger Info

Tesla is now showing users information about nearby Superchargers. When you’re near a Supercharger, Tesla will now highlight it at the top of the Tesla app, letting you report issues or view site information.
This could be useful when a driver is trying to locate a Supercharger or simply needs to report an issue.
Robotaxi Mode

It appears that Tesla’s Robotaxi network will utilize the existing Tesla app rather than relying on a dedicated Robotaxi-specific app. New code found in this update suggests that owners will be able to switch between ‘Fleet Mode’ and ‘Owner Mode,’ allowing them to choose whether their vehicle joins the autonomous taxi network or is reserved for personal use.
Child Left Alone Detection

Tesla’s upcoming child detection feature will let the vehicle automatically turn on its climate system if it detects that a child has been left alone in the vehicle. Tesla is also introducing other safeguards, such as sending notifications to the owner and calling emergency services if needed.
Tesla is now beginning to integrate this into the Tesla app, according to a tear-down of this update by Tesla_App_iOS. If a child is left in the vehicle, the owner won’t be allowed to turn off or change climate settings.
Tesla is also preventing other things, such as installing software updates, while a child is detected alone in the vehicle.