Andrei Frumusanu, AnandTech:

This year’s new iPhone 13 series have been extremely promising in terms of battery life as Apple has improved this aspect of the devices through a slew of different improvements. All the new phones feature new generation displays, most notably the new Pro models which have new variable refresh displays, along with increases in battery capacities. After a few arduous days of battery life testing, we can come to some very positive conclusions.

There’s a detailed discussion of LTPO VRR. If that’s just alphabet soup to you, here’s a bit from this discussion of LTPO:

LTPO is the snappy acronym that stands for low-temperature Polycrystalline oxide. In short, it allows for a display to dynamically change its refresh rate without needing any additional hardware components to sit between a device’s graphics processing unit and the display controller.

And VRR is variable refresh rate, which is being branded as ProMotion. Apple’s rates vary from 10Hz to 120Hz.

If the screen discussion doesn’t grab you, scroll down the the section labeled “Bigger Batteries”. The first table compares battery capacity of all the iPhone 12 models to that of the iPhone 13s. Big jumps (ranging from 8% to 18% across the board) in every model.

Next up is a bar chart showing web browsing battery life (in hours) for a variety of phones. From. the description:

All the new phones showcase extremely large generational gains compared to their predecessors. For the iPhone 13, we’re getting results that are 34% better than the iPhone 12, which exceeds the +14.6% battery capacity increase. The new SoC efficiency as well as increased display power efficiency would explain the remainder of the difference.

The iPhone 13 battery life is a big leap forward.