In Android 5.0 Lollipop there is a way to enable a grayscale type mode and it is present in most, if not all, custom ROMs that are built upon AOSP.
Grayscale mode is interesting because it removes all of the color from the images on the screen. This doesn’t mean much for those devices that use an LCD display(unless you just like the look of this grayscale mode) but for AMOLED displays it can help to preserve battery life. This is because AMOLED displays use a different amount of battery power depending on what color the display is showing.
For example, if you have an all black screen, then there shouldn’t be any(or hardly any) power used at all to light up that screen.
This is because the screen isn’t lit up at all. Alternatively, if you have an all-white screen then your AMOLED display is pushing as much power to light up that screen as it needs. If you have a screen that is half white and half black, then it will use half as much battery power to light it as it did for the white screen. This varying degree of power usage happens in different colors too. It takes more power to light up a bright yellow screen than it does to light up a dark blue or dark red screen.
As you can tell, it can be beneficial for AMOLED devices to use a grayscale mode to conserve battery life. Devices like the Galaxy S5 and Galaxy S6 can go into grayscale mode if you activate the Power Saving Mode and Ultra Power Saving Mode.
Enable Grayscale Mode
- Enable Developer Mode
- Launch the Settings and Tap on the ‘Developer Options’ Menu
- Scroll Down Toward the Bottom and Look for the ‘Hardware Accelerated Rendering’ Section
- Tap on the ‘Simulate Color Space’ Option
- Tap on the ‘Monochromacy’ Option
Explanation
To start this off, you’ll need to enable the developer options from within Android. Simply follow the guide linked in the tutorial above and that will show you how to enable this secret menu within Android. Once that mode is enabled, then you will see a new menu within the Settings of Android called Developer Options. Tap on this menu and then you’ll see dozens of different things that you can tweak. Be careful here though because turning on something and forgetting what you did can make it frustrating to find out how to revert it.
Scroll down in this menu and look for the section for Hardware Accelerated Rendering. Within this section, which is located toward the bottom, you’ll find an option called Simulate Color Space. Tap on this menu option and you’ll be given four different things to choose from. One of these is called Monochromacy and if you tap on it then it will be enabled. While this feature is enabled, images on your phone will appear as if you had enabled grayscale mode.
Now, I do want to point out that this might not actually be doing anything at all. As the Settings option says ‘simulate’ which makes me believe this might just be making the appearance look like it is in grayscale mode but nothing is actually changing under the hood. For instance, if you take a screenshot, your screenshot will be in full color. So if you have an AMOLED display and you are curious about this feature then you can experiment with it. I am curious to see what your findings are.
Well written, thanks! The power saver grayscale feature is one I miss from the stock firmware. I wonder if there’s a way to either make a shortcut so it’s quicker/easier to enable/disable, or if I could put it on a trigger?
Thanks Eric 🙂 and you’re very welcome. I’m not sure if that is possible. You might be able to create an activity shortcut with Nova Launcher or something. But I’m not really sure
If you figure something out though, please come back and let us know
My phone Samsung galaxy j7 slows and lags when I turn grayscale on. Is this normal??? It does get a bit fast when I turn 2d rendering on. I did it a few times and everytime after some time (in don’t remember but it wasn’t too little) it froze and restarted and when it froze it just didn’t get bricked but like became zzzzzzzz with the video. I mean kept on repeating the zzzzz and restarted.
If you boot the Galaxy J7 into Safe Mode, is it still slow and laggy when you enable grayscale mode?
No much battery improvement since it is only simulating monochrome colors after processor pushing all colors on screen. Processor has extra burden even though AMOLED save some juice.
I don’t know exact numbers (since display and CPU efficiency changes each generation), but the display does use way more battery than the CPU
Hi. Thanks for the explanation. By the way grayscale also has a psychological effect on one’s brain and helps them stay away from the phone instead of the coloured which attracts more people
You are absolutely right. I’ve seen an interview with an ex-Google employee talk about this very specific topic. That’s another good reason to use this feature 🙂