What smartphone has the longest battery life?

The smartphone with the longest battery life is highly dependent on the usage pattern, the settings of the phone, and the apps running on it.
However, some smartphone manufacturers make special emphasis on battery life and have models that have large battery capacity and efficient power management systems.
As an example, some smartphones that have been known for their long battery life include:
The ASUS ROG Phone 5 has a 6000mAh battery and supports fast charging, which can provide up to 12 hours of gaming time and up to 2 days of general usage.
ROM stock / raw cho Asus ROG Phone 5 (ZS673KS) https://t.co/AqbL4PnxiS
— iTeam OS (@iteamosvn) January 25, 2023
The Motorola Moto G Power has a large 5000mAh battery that can provide up to three days of battery life on a single charge.
Moto G Power | 2022 | 3-Day Battery | Unlocked | Made for US by Motorola | 4/128GB | 50 MP #Camera | I
— boqli (@boqli1) January 18, 2023
$169.99https://t.co/BOmYBSMsnB
The Samsung Galaxy M51 comes with a massive 7000mAh battery that can provide up to 2 days of battery life on a single charge.
Samsung Galaxy M51 starts grabbing the latest security patch update of 2023 https://t.co/ijwr40Es9x
— Sam Lover (@samloverblog) January 25, 2023
It's worth noting that the actual battery life of a phone can vary depending on how you use it and the settings you have, such as screen brightness, background apps, and cellular or Wi-Fi usage.