What settings and app permissions boost flagship battery life?

[George.J]

I recently upgraded to a flagship smartphone, but I'm disappointed that the battery barely lasts a full day with my typical usage, which involves a lot of email, messaging, and about two hours of navigation. I've already turned down the screen brightness and disabled obvious battery hogs, but I feel like I'm missing more nuanced settings. For power users who have successfully extended their daily battery life, what specific system settings or app permissions made the biggest difference? Are there particular background processes or connectivity features like Bluetooth scanning or location services for unused apps that are silent drains? What's your realistic routine for managing battery health over the long term, and do you find battery-saving modes actually useful or do they cripple the device too much?