Back in 2016, my primary smartphone was Xiaomi Redmi 3 with Android 5 / MIUI 7. Amazing ~$120 budget phone back in it's era. I still get all-day battery life even today. I live in US so I had to import back then, I still don't regret it lol
Unfortunately, between 2018 and 2023 I did not enjoy using this phone. By 2023 it was put away in a drawer…
However, just last month I was able to turn it into the most comfortable mobile device I own that ALSO now has the ability to run modern apps.
The caveat: I can't actually switch back to it as a "real phone" because of the US 3G shutdown (it never supported LTE bands here), but aside from that it's an incredible "tablet".
TLDR:
Old Android phone. Snapdragon 616 chip + 720p IPS display. LineageOS 18.1 Android 11 ROM. (Unofficial port if that matters.) Disable HW overlays. Disable it again after rebooting or if the battery runs out. I can now enjoy modern apps with close to no strain.
Here's the full details…
Part 1 - some backstory before I get to the current situation.
(Skip to Part 3 if you just want to learn how I fixed it)
Just to note, I've totally forgotten how the original MIUI 7 software felt in regards to screen comfort (honestly if I really try to remember I think it's likely it was quite comfortable)
Anyway, at some point in 2018 I decided to try out some custom ROMs. Back then a weird quirk was that if you ever tried returning to MIUI, your bootloader could get locked again, it took forever to get an unlock request approved so once you started flashing ROMs it wasn't easy to "safely" return to the original OS.
This means up to 2023 my main point of reference for how this device feels has been the custom ROMs — LineageOS 14 on Android 7, Pixel Experience on A8, CyanogenMod on A6, even an alternate Chinese ROM (Meizu Flyme OS on A5.1)
Part 2 - the problems:
After I first became aware of how significantly screens affected my health during 2022-2023 (to be more specific, after a 2021 14" mini-LED MacBook Pro nearly ruined my life)… one of my first ideas was to see how many daily tasks I could feasibly move back to any older + more comfortable devices I still owned.
Unfortunately at the time, there seemed to be problems across the board with my old Xiaomi.
Running the Pixel Experience ROM, even though the image was "mostly" flat in a good way, I would get a very strange sharp pain in my eyes after a few minutes of using it. Some colors, especially reds, also felt oversaturated and as if they were "pulling" at my eyes. On this ROM I tried Disable HW overlays in Settings and it didn't change anything.
I then tried hopping between the previous ROMs I tried and the issues remained. I thought the Android 5 Custom ROM could possibly fix things as many people here only started having problems with phones after Android 6. Unfortunately this didn't work and actually seemed to make the pain even worse.
(I didn't want to try the original MIUI 7 ROM again for fear of accidentally locking the bootloader, especially because this device is years out of support so I have no idea if I would even be able to unlock it again)
At this point I was stumped. Over the years my Xiaomi also developed a defect after a screen crack where a strange greenish glowing affect along with a repeating pattern of small squares is constantly visible around the edges of the LCD, so I really wasn't sure if my problems were coming from the defective LCD itself or the software.
But then…
Part 3 - the solution:
For a while I thought custom ROMs for this phone simply maxed out at Android 8-9ish as that's what I was seeing on the main XDA page. However, just last month after digging deeper out of curiosity, I was shocked to find a link to an unofficial LineageOS 18.1 port, based on Android 11 from 2020, buried in one of the threads. ("Official" ports of LineageOS stopped after Android 8)
My first thought was "newer version = bad" but I decided to flash it anyway. Right out the gate I noticed that the screen felt different in an interesting way. However, at first, I still felt some immediate eyestrain similar to what I mentioned before.
Then… not even expecting it to work, I headed to Settings to Disable HW overlays (as I've previously tried on other ROMs to no avail).
Boom.
STILLNESS. STRAIN GONE.
Toggling it back and forth, even just scrolling the super basic looking developer settings menu with text and toggles felt entirely different to me. It feels like I can now keep the entire screen in focus while I scroll instead of the scrolling "pulling my eyes around" in whatever direction it's moving.
One time the strain came back after the battery ran out. Turns out Disable HW overlays unchecks itself every time the device does a full shutdown or reboot. All I need to do is re-check it and my eyes feel great once again.
It's been around a month now since I solved this. Waited to post until I knew it wasn't placebo.
With Android 11 I can actually get modern apps on this phone for the first time in YEARS so I've loaded just about everything that doesn't absolutely need my iPhone or a cell signal.
Discord, Instagram, DoorDash, Apple Music, email, calendar, todo apps, Obsidian, whatever, I run all of them here now. I can read for hours and feel FINE afterwards. Sometimes my eyes even feel better i.e. heightened depth perception in the real world.
Obviously in 2024 with Snapdragon 616 it's not fast by any means but it's not painfully slow either. Apps take a while to load but once they're open it's smooth enough.
I'm typing this whole post on my Xiaomi, I have 47 other Chrome tabs and 3 other apps cached in the background and there's no typing lag, although at times it hangs for a few seconds when switching tabs.
(In addition, loading screens are surprisingly SO much less anxiety-inducing on a comfortable screen, I can stare at a loading spinner or a frozen screen in almost a "relaxing way", compared to "bad devices" like iPhones where I usually get sudden discomfort or a strange feeling of wanting to look away if the screen freezes """still""" but is "actually still moving" due to temporal dithering and such)
One small detail, Battery Saver mode feels better to me for whatever reason. Not sure if this one is placebo. However, the rest of my experience such as the effects of Disable HW overlays on Android 11 is NOT placebo for me at all.
IN CONCLUSION:
Got an ancient Android phone? Does it have a Snapdragon chip and an IPS LCD display? Does it have an unlockable bootloader?
Try flashing a LineageOS 18.1 ROM if available. Dig for an unofficial port if it doesn't initially seem possible, I thought Android 11 was totally out of the question for my phone until I found what I did.
Then Disable HW overlays. Disable it again if the phone reboots. You might be surprised.