Immediately turn off this battery-draining, 4G-consuming feature on iPhone
Since iOS 9.0, Apple has introduced a feature called Wifi Assist on iPhones. This feature is beneficial in many situations as it automatically switches the internet connection of iPhones and iPads from Wifi to 4G/5G mobile data when the Wifi signal is weak or unstable.
However, Wifi Assist can also lead to unmonitored consumption of 4G/5G mobile data, making it hard for users to control data usage and battery life, especially when the battery is low and not being charged. Therefore, turning off this feature can help extend battery life.
Wifi Assist is a default feature on iPhones that activates when the Wifi signal is weak, automatically using mobile data to improve the connection. To save data, you can turn off Wifi Assist by going to Settings > Cellular > Turn off Wifi Assist.
After temporarily disabling Wifi Assist, your iPhone’s battery life can be extended. However, if you have sufficient battery and need a stable connection for browsing, watching movies, or playing games, you might consider re-enabling this feature.