I am still using an iPhone 4. Out of five iPhone 4/4s I bought only two are usable. The three other ones triggered eye strain in just a few seconds.
However, the iPhone is getting slower, and the screen size is not really what you use nowadays.
Do you have a Smartphone with current technology that is perfectly usable throughout the day?
I use a Note 3 SM-N900W8 (purchased Oct 24th 2013, was having issues with PWM then, got a migraine from being in the store too long 
)
I never bothered to check for PWM as it was less of an issue in phone displays back then but I never had problems with the display. Recently checked with Canon T5i and it shows up as higher frequency than usual >300hz which is a safe zone normally. And I cannot detect PWM using pen test (insert S-Pen joke here)
However Samsung phones made in 2014 and after have terrible PWM worse than this. Friend got a headache from trying the S5 in store, think later batches of the Galaxy S4 may be affected, etc.
I am iPhone 4s with iOS 7.1.2, and it's smooth enough because I don't usually use apps on it. (I surf the web on computer)
I think iOS 6 is better on iPhone 4. :>
JTL I hate Samsung mostly because of the screen. The same feeling as yours.
I've got a LG LGL34C for about a year now and haven't had any issues with it. Dunno if it's fast or not but it's usable... so that's good enough for me!
Did anyone try the BlackBerry Leap?
I use an iPhone 4s and I hate it It gives me instant eye strain + headaches.
Its original OS (I don't remember which one it was) seemed a lot better than the new updated ones. I wish I could revert it back to how it was.. but oh well.
Yes, that is true. I had to downgrade my iPhone 4 to iOS 6 because on iOS 7.1.2 I got severe eye strain and headaches. I switched back and forth several times to be sure.
I think there is a newer hack tool that allows you to downgrade iPad 2 and iPhone 4s to iOS 6.1.3. I read about it in reddit's jailbreak section. I believe it is called something like Odysseus. But I can not guarantee that it is safe to use and free of malware.
I think iOS 5 was the original OS.
Also I might be able to go to a phone store soon with my fast shutter speed DSLR to test for flickering in newer smartphones.
Also people on my family also own, alongside the Samsung's I mentioned.
)will test those later.
I tried the BlackBerry Leap now. It is not the worst LED device I ever used, but it still starts to hurt a little after 1-2 minutes. At night the minimum brightness is a little too bright for me.
I just found this website:
http://www.phonearena.com/phones/benchmarks
It lists the minimum brightness of a lot of phone models. A value of around 5 nits (nit = cd/m²) is very good for reading at night without ambient lighting, which I know from my usable monitor, iPhone, and iPad.
Probably not everyone needs a very low minimum brightness (in addition to other factors), but if you do, this list might prevent bad buys.
Please let me know if you get a chance to test the iPhone 6s. It would be much appreciated!
I have the HTC One M8 and it on the lowest brightness level + the brightness lowered further with the max lowering settings on the "Twilight" app. It is very easy on the eyes this way. I do not know if it is PWM free, but someone on the Apple thread said it was. I will try and dig up the post.
I do, but I don't know what to look for.
degen See my ASUS monitor video as an example. Keep speeding up the shutter while recording to make the PWM frequency "out-of-sync" with the camera shutter speed. Darker the image = the better.
https://www.ledstrain.org/d/5-asus-ve278q
Nexus5 PWM test is in
It passes 
Filmed at 1/4000 shutter speed until 00:40 and iSO6400
https://youtu.be/PH8bMS5RUzIThis is so horrible:
I recently bought a BlackBerry Z10, it was perfectly usable, no eye strain at all for hours. Then I upgraded the OS to the latest version, and right after the initial boot I got burning eyes and very strong eye strain. I looked if I can downgrade the OS - no, it's not possible. It was possible for years, but not anymore with this latest version. This is just horrible. Such a luck at first, and now it's all gone.
