Ah, summer… the best of all seasons. That is, if you live in an area where it’s really hot and you have a liking for the sand and sea – otherwise you might see things differently. But whether we head to the sea out of excitement or are forcibly drawn there by external circumstances, it’s time to head to the beach where most of our team call home.
We have no doubt that you’ve experienced the ill effects of sunlight and the heat that comes with it on your phone’s display brightness and battery life, and we’re no strangers to them either. Still, we had no numerical representation of how much a phone’s longevity suffers under these, in many ways, unfavorable conditions – subjective assessments from others or anecdotal reports don’t quite matter. So we thought we’d do a little test.
As a general rule, every attempt to approximate a real-life phenomenon with some kind of engineering model is bound to have flaws. We thought hard about how to simulate smartphone use on the beach, then did some preliminary testing of different setups, and here’s what we came up with.
We placed the phones in the sun, with no shadows or anything. For an initial attempt we placed them under a diffuser (to mimic a beach umbrella) but this gave unsatisfactory results when it came to maximizing the ambient light sensor and increasing the actual maximum brightness of the phone (at least as long as it maintains it).
The ambient air temperature was 30°C (86°F) and the test surface where the phones were placed reached temperatures in the mid-40s (about 115°F). There was a medium-strength wind blowing during the test, and it was also cloudy every now and then, interrupting the torture for a minute or two – most welcome conditions that brought our setup closer to the reality we were trying to simulate.
We picked four phones from different walks of life, with some additional reasoning behind our selections. For example, the Galaxy S24 Ultra is, in a way, the pinnacle of smartphone display technology – thanks to the glass on top of the actual display. The Vivo X100 Ultra, despite being released only in China, has one of the highest peak brightness levels we’ve measured in our usual testing routine. The Poco F6 Pro and Motorola Edge 50 Pro, meanwhile, are representatives of Team Mainstream – relatively affordable handsets for the masses (as opposed to ‘photography enthusiasts’, or ‘mobile gamers’, or ‘fashionistas’, or ‘choose your own label’).
We laid them face down on the test ‘bench’ for half an hour so they could adapt before starting the test – you know, you come to the beach, have a cup of coffee, go in to test the water temperature – then start scrolling without thinking. Since they are all light-colored, the adaptation process did not harm any of them.
We then flipped them over, set the brightness to Adaptive/Auto, and ran our usual web browsing script, interspersing the regular pages with an additional page that is plain white – for intermediate brightness measurements. The ROG Phone 8 Pro was tasked with capturing this process on a timelapse video.
As it turned out, by the time we actually started testing, 3 out of 4 phones had already heated up so much that they didn’t want to increase the brightness to the actual maximum – only Motorola did so.
In fact, the brightness behavior plots are an interesting topic in themselves, but we will summarize them for you. About 5 minutes into the test the Galaxy dropped slightly below 300nits and stayed there throughout the test.
The Motorola went the brightest during testing, staying at 1300 nits for about 15 minutes, then 700 nits for another 15 minutes, and settling at around 530 nits after about half an hour.
Vivo started the test at 470nits and dropped to 330nits after 20 minutes, where it remained till the end.
Poco was happiest at 455nits, which it achieved about 3 minutes into the test after hitting 785-nits.
With that in mind, here’s what we found in terms of battery life from our test subjects. For comparison, we have the phone’s results from the regular review process, where testing is done at a standardized brightness of 200nits.
Battery life, web browsing test, (h:mm)
Galaxy S24 Ultra
Vivo X100 Ultra
Motorola Edge 50 Pro
Poco F6 Pro
Standard Test
Beach Trials
In a way, the results of this test came as a surprise to us, as our general impression was that our phones drain much faster at the beach than with ‘regular’ use. You could say that the disproportionately larger drop in the case of the Vivo compared to the others is what we expected. But it proves to be an exception in this diverse (if admittedly small) sample group.
You’ll have to trust us on this one, as it’s essentially impossible to capture it in a photo or video, but all phones were easily readable throughout testing. This is another anecdote we were trying to avoid, but it’s difficult to convey in visual form. Phones also have additional different ways to deal with bright ambient light, other than increasing display brightness, such as the Galaxy’s anti-reflective glass or sun-specific tone curves.
We’ll be quick to admit that our testing involved a lot of variables, and while it may be marginally representative of the use case we were trying to simulate, it may be far from the way you spend your beach days. It’s hard to measure, isolate, and control the impact of shade, ambient temperature, wind, frequency and duration of use, the app actually being used, and who knows what else.
Summoning our inner philosophers, we’d conclude that if you’re out in the sun, you should probably enjoy it and not waste your time on your phone. But it’s nice to know that your smartphone will be there for you when you need it – whether it’s sunny or not.
