This is more of a RANT than anything else. The battery in my iPhone 6 is complete RUBBISH....if I FULLY charge it overnight to 100%, it's normally at about 20% by about 12:30 in the afternoon. It doesn't take long to go flat after that. Even if I fully charge it before going out of an evening, it's often flat by the time I get back. I use low power mode all the time. Any other decent tips to help extend the battery life? I know they are not fantastic anyway being quite an old device now.

Cheers, Gab