We all know that the battery power of the iPhone will be pretty low at the end of a day away from a charger, so how can we maintain its charge when we don’t have one of those pesky white cords handy.
First off, reduce brightness. This can be done by accessing > Settings > Brightness. Make sure that auto brightness is switched to off.
Another one is disabling location services. This can be done through Settings > Location services.
Although this will prevent you from accessing all data, enabling Airplane mode saves a lot of power. This can be done through Settings > Airplane mode > On. Once Airplane mode is enabled it is still possible to connect to Wi-Fi if a connection is available.