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What an "Always-On" display means for battery life on Android

As more leaks and rumors flow forth on upcoming Samsung and LG phones, it's easy to become prematurely concerned about what it all might mean for the battery life of these not-yet-announced phones. The Galaxy S6 and S6 edge were not exactly battery life powerhouses, compromised by the quest for thinness and the demands of physics. News of software that will intentionally keep the most power-hungry part on any phone — the display — up and running on the Galaxy S7 may not sound great to those who don't want to reach for a charger every couple of hours. Meanwhile, LG users who have lived with the double-tap to wake setup may find the new interface on the G5 an unwanted step away from what they are used to.

While it's going to be at least a week or two before we've got hands on these phones at MWC 2016 to know for sure, there's a good chance Samsung and LG have a whole lot more to show us than the leaks suggest.

In many ways, Always-On is the natural evolution of existing display ideas.

First things first, let's break down what we're talking about when we say a display is "Always-On" in this context. Much like Motorola's Moto Display and Google's Ambient Display, Samsung and LG are referring to a breathing, black and white representation of information on the screen. Always-On mode will give you a glimpse at the time, recent notifications, and probably one or two other things we've not heard about yet. It means you don't have to wake the screen to see what that notification tone or vibration was, and it means you can just glance down at your phone to get that information. Samsung played with this idea last year with their edge display notifications, and LG's use of a second screen on the V10 demonstrated how they view notifications when the primary display is off. In many ways, Always-On is the natural evolution of existing display ideas.

So does an Always-On display mean more energy is consumed during the day to deliver that information to you? In most cases, no. The idea is you'll be using the breathing notification instead of constantly waking your phone, which means your phone can stay in a low-power mode to deliver you this information. If this feature only stops you from waking the phone three or four times a day, you'll still be net positive in the amount of power consumed. Also, Samsung's use of AMOLED displays means only a handful of pixels are given power to display information to you. LCD panels still have to light up the whole panel to deliver you information, but as we saw with the Moto X Pure Edition this past year the difference in power consumption is still quite low because the phone doesn't have to go from low-power to fully active to deliver you that information.

Ambient Display

Google's Ambient Display works without changing the way you interact with things like notifications, but the images and descriptions we've seen from LG suggests the G5 will be packing something a little different. You'll get that glance at the display, but the notifications look to be just icons through the case and there's a Moto-esque gesture to get more information. This sounds cool, and again we still don't have a full official explanation, but that raises some double-tap to wake concerns.

It's possible LG will set it up so you can have one or the other, but there's a good chance you won't be able to do both. That may be a good thing, after all Motorola has demonstrated some incredible things with their display software, so it's probably one of those things we'll have to see and touch in order to fully appreciate.

Basically, there's nothing to worry about just yet. Power consumption isn't likely to be an issue, and all signs point to this being something more functional that what these companies are using now. All we need now is for these phones to get here, so we can stop worrying about things that we haven't really seen yet.

Russell is a Contributing Editor at Android Central. He's a former server admin who has been using Android since the HTC G1, and quite literally wrote the book on Android tablets. You can usually find him chasing the next tech trend, much to the pain of his wallet. Find him on Facebook and Twitter

78 Comments
  • Bye-bye battery Posted via the Android Central App
  • Not really... Posted via the Android Central App
  • Someone missed the point of the post hehe. Russell does have some good arguments on why this is probably not a battery killer, and since it's been done in the past by others, it's even more validated. Heck, even way back with the S2 and its notorious lack of notification LED there was the app NoLED that displayed notifications on the screen constantly and because of AMOLED the impact on battery was not that bad... and we're talking eons ago!
  • Ha I remember that app. That thing was ugly.
  • I thought it was cute haha. I liked having the app icon floating around in the screen as a notification since I didn't have the LED. And if you think about it, it was one of the first (if not THE first) to start the whole 'Notification Preview on the screen while off' thing. If it were Apple that guy would be getting a ton of money in royalties right now.
  • Actually, I'm seeing it from this perspective: companies are now getting more and more confident in their batteries, enough that they feel that even adding this won't make a noticable difference to upgraders.
  • Did you READ the article? Without actually having and testing the device, it's inconclusive.
    Second, don't you think (heh, maybe not), that they'll have a toggle to turn it OFF?!
  • As long as it can be turned off, they can put it in my phone if they want. I'll probably disable it. Don't like to see constant stuff on my screen for curious eyes to see, and of course wouldn't want this AT ALL in a theater.
  • I have the V10 with the Second Screen always on. It's not that bright so no "glaring" issues with peeking at it in the theater. And there's a setting to tell it to hide sensitive information.
  • When is someone going to put this on the BACK of the phone, so I can leave it resting face-down on the table when I'm at the bar? At least throw a notification LED on there for me.
  • It's easier to just leave the phone face up at the table, isn't it? Posted via the Android Central App
  • Not if it has a camera bump.
  • But the notification LED would still be on the front of the device, not the back.
  • I'm saying put a second notification LED on the back, so I can leave it face down.
  • My LG G2 has a notification light on the back and front. The one on the back is actually the power button and is rather bright really. Posted via the Android Central App
  • I wished they brought that back...
  • They did it with the Yotaphone.
  • Why would anyone want to leave their phone face down and damage the screen? Anyway there is Accessibilty Settings that already allow what you ask for in all Androids and iPhones using the camera flash to alert you to notification Posted via the Android Central App
  • I don't get people who rest their phone face down. It' SO easy to scratch the screen that way. One errant bit of grit on the surface, the phones slides just a little, boom you have a scratch. I don't get even the point of this, have it face side up, anything happens and you can see what's going on, don't need to lift it up and turn it over.
  • Wait, you put your phone face DOWN on a BAR? Hope you carry protection.
  • I may use it for few days maybe a week. Then disable it. Just like the dual screen mode, air gesture mode..etc. Posted via the Android Central App
  • I thought the exact same thing but 4 months on I'm still using it and wondering how I got by without it before! Agree on those other features, I don't use them at all but for me at least the 2nd screen is great Posted on LG V10 via the Android Central App
  • I still think an OLED display is the best fit for this. While the difference in energy consumption isn't all that big, I would still prefer the use of OLED for a feature like this.
  • If the difference is minimal then what's the benefit? Just personal preference? Posted via the S6 Active
  • On my V10 I notice the light bleed from the second screen into the main screen. Not a big deal but still drives me a little batty when I notice the lack of light isolation. On my SO's S6 Edge, the edge displays the clock with no light bleed up into the flat parts of the screen. When comparing them side by side in a low light room (which is 90% of the time I use my phone) it makes the V10 look cheaper. Screen quality is a big issue with me and light bleed is just unavoidable on LCD. If always on was done with the full V10 screen (damn the battery,) then I would have a flashlight on my nightstand (once my eyes adjusted so ymmv.)
  • That's precisely why. It's not much of an issue when there is light. But in the dark, it's quite obvious.
  • The light bleed is quite noticeable, it's my only (very minor) complaint with the 2nd screen. It does however help you find your phone in a pitch black room! Posted on LG V10 via the Android Central App
  • Wouldn't burn-in be an issue though?
  • If it's pulsating, then no. It won't be.
  • Burn-in is a problem only with Amoled displays. VZW Moto X DE/N7
  • Actually, it's a problem with every display, from CRT and Plasma to OLED. It's just that OLED is more susceptible to it than LCD.
  • The way the LG G4 works now is perfect, put your finger on the screen when off and pull down and you get the notifications, time etc.. I personally don't want my phone breathing at me and we don't even know if that's the case with LG Always On. For all we know at this point it could mean exactly as it says, Always On! Either way I hope you can turn it off. Posted via the Android Central App
  • I enjoy this feature as well. Posted via the Android Central App
  • It's likely to be very similar to the 2nd screen on the V10 and you can turn that off. It also turns off in pockets and bags etc Posted on LG V10 via the Android Central App
  • Finally catching up with Nokia, uh?
  • People used to think I had stuck something on my Lumia 925 when they saw the time. I used to love that feature.
    Motorola's implementation was a little better though.
  • My ambient display activation on the N6 is too inaccurate, had to turn it off. I prefer to root and run lightflow with it's hidden LED. Not rooted right now but, the OG moto 360 I picked up is a great "second screen" for notification so I guess it all worked out right? I'll keep rambling on and say I wish this thing had IR sensors so I could move my hand over to wake. Alright I'm, done now lol
  • It's also inaccurate on the 6P. The thing hardly ever works,
  • I'm giving ACDisplay a try on my 6P. Will post results in the forum after a few more days
  • Ambient display sure looks nice but is crap. It has a mind of its own lol
  • Excellent article. I've seen a fair few comments on here suggesting that a second screen will mean battery life will take a hit but as the article says, if it saves you powering up the whole screen just a few times a day it's the opposite, you'll actually get more battery life. That's certainly what I've found on the V10 anyway. Wasnt at all convinced it'd be anything more than a gimmick but I find it not just prolongs battery life but is actually really useful too. Would take one hell of a phone to make me consider giving it up now! Posted on LG V10 via the Android Central App
  • 4 more days till that s7/g5 announcement.....can't wait!!! Posted via the Android Central App
  • Same. I am looking forward to that day more than I was the superbowl and I'm a football fan. Posted via the Android Central App
  • I hope they offer a way of turning this off. I don't like it.
  • This is a great feature to have on a phone. I have the sony smartwatch 3 with an ambient mode, and it lasts 2+ days on a tiny 420mah battery, so I'm guessing a phone battery will hardly take notice. This plus transreflective display (which the SW3 also has) on a phone to improve readability in direct sunlight would be fantastic.
  • On the Nokia phones I've owned the battery barely took a hit. I set it to always on and the battery lasted a day and a half no problem. On android it will probably suck.
  • As a couple have mentioned, Lumia phones have been doing this for a while with "Glance". Works well and one of the few features I miss in my move from Windows phone. I can only assume they're bringing new baked in tech to the Android implementation, otherwise nothing ground breaking here. But... Will be nice to see. Posted via the Android Central App
  • I miss the hell out of active notifications from my OG Moto X. By far the best feature I've ever seen on a phone. Then a friend of mine went to work for Samsung and I got the latest and greatest devices for a significant discount. But they only have a notification light. Been looking for a way to do the active display, but all the 3rd party apps suck. I would almost go back and pay for a Moto phone to get it, but then Moto made their phones humongous, so I'll stick with the 'cheap' Samsung. I haven't heard of Samsung allowing Google's ambient display or creating their own, but I wholeheartedly support it. Seriously, give me this feature.
  • have you tried AcDisplay? I used it for my Note 3 and found it quite useful.
  • I tried a few of the better ones and none of them seemed to work correctly. They would keep the screen on or wake the screen up when it wasn't supposed to be on and kill the battery.
  • I have the LG V10. and I have the Second Screen always on. Doesn't affect the battery life all that much though I admit I've never had it turned off, I might try that sometime. But I find it quite useful to see at a glance what apps have active notifications on by their icons. If it's something I might be interested in I just double-tap on the main display to turn it on. Basically the Second Screen drastically cuts down the number of times I have to turn on my phone's display just to check the date/time, battery life and to see if I have any notifications. Then add in the ability to toggle the flashlight, wifi, and vibrate mode or control music playback all without turning on and unlocking the phone. With the phone unlocked, the Second Screen is useful for app shortcuts (I have the LG Remote to control my TV and settop box) and calculator on there for easy access. Plus when I'm inside an app I don't get those Android popups for notifications that I have to swipe away, they just appear on the Second Screen and out of the way. Quite useful when I'm playing games or watching a movie. It also serves to contain more buttons in the camera app. All in all, quite a useful feature and makes me feel good about my purchase.
  • This sounds like a cool feature. I really like Moto Display, and I don't notice any battery issues with it. Posted from my Moto X Pure Edition via the Android Central App
  • Nokia still cast a long shadow over the industry... Their camera tech (particularly in the 1020), their early adoption of Qi charging...Glance... In many ways they were before their time. It's a genuine pity Windows Phone (with all its failings - mostly on the app availability front) never really captured the Zeitgeist to give Nokia the opportunity to really shine. If the next Galaxy phone can also be used as a hammer...I feel a lawsuit coming on! Posted via the Android Central App
  • You got me all nostalgic about my Nokia Lumia 925 and WP :(
  • Glance screen was implemented on my 3 year old Lumia 920 and battery life has been fine, barely noticeable difference. Posted via the Android Central App
  • I know an easy trick for this feature on all phone. Simply press the power button. Come on! Is it that hard? This is just a gimmick to me. If you're close enough to see your display then you're close enough to spend 0.2 seconds to turn on your screen. Google Nexus 6P
  • You might press that power button dozens of times a day, waking the screen in the process and wasting battery. With a "Glance" screen. The idea is that you look to see the time, or whether you have any notifications, and if you don't need to open up the device properly (waking the screen and CPU) it instead goes back into the pocket, saving time and power (anecdotally enough to at least cover the power needed to keep those low brightness pixels lit). On Lumias, the "Glance" screen can also be set to only wake upon accelerometer activity, further reducing battery tax. Think of it as a more informative notification LED. Posted via the Android Central App
  • Yeah? Start using it, then have it taken away and you'll see how much of a gimmick it is. I had it on my Lumia 920, and moving to my S6, it feels like one of my hands has been chopped off. You get used to just looking at your screen to check the time, no need to turn the phone on just to check it, or just to see what that last notification was actually for.
  • You can also say a teenage girl cannot live without social media. It feels like part of her just died. Google Nexus 6P
  • Being enjoying glance feature since many many years on nokia phones...its such an awesome and needed feature...soo easy to see all yr stuff without touching yr phone...i have 950 ds and lg g4...good to see android trying to catch up after soo many years....the good part of amoled only pixels light up to show info Posted via the Android Central App From My awesome LG G4
  • My old Sony-Ericsohn feature phone, on which BTW I did not much less than I do with my "smart" phone!, I could see the clock all the time. The screen was (partially) active but the back-light was not. There was a reflective coating behind the screen to enable this. A very costly!! feature that has since become extinct. Bring it back! Partial screens abound now. But it takes wakelocks to work them, even if less back-light or amoled pixels are activated.
  • It's not extinct. Sony still use it on the Sony Smartwatch 3 for the 'transflective display' Posted via the Android Central App
  • Glance Screen was one of my favourite Nokia Lumia features and now that coming to the G5 along with moving those stupid buttons from the back onto the side has definitely got my interest. Think I'll be trading my much loved S6 for the G5 soon Posted via the Android Central App
  • Does no one want to mention Windows phone glance feature.... Windows has had this feature for 3 years or so... I had it on my Lumia 920 and it did hurt the battery some but it's functionality benefits outweighed it's battery usage Posted via the Android Central App
  • Lol. Read the comments again.
    It has been mentioned half a dozen times before your comment ;)
  • Has everybody forgot about Nokia and Microsoft's Glance Screen? You can have it set to either: turn on for thirty seconds at a time after detecting motion; turn on for fifteen minutes at a time after detecting motion; or to always be turned on. Always on. Nokia and Microsoft have had an always-on display for years. I would just like to point that out. Oh, and battery life loss is negligible. With Glance Screen set to always on, double-tap-to-wake turned on, all the extra features turned on, etcetera, my Lumia 830 still gets significantly better battery life than a Galaxy S5 or Galaxy S6.
  • Is Motorola's wave you hand over the screen patented? I have a Moto X 2014 that I simply loathe, but that was a nice feature. Nicer than my S4's coloured light.
  • Even if it had 0 impact on battery, **** if it made my battery last longer, I'd still turn it off. I find it extremely annoying. If i wanna see what's on my phone, I'll just click the button. Takes half a second and doesn't have my personal info on display for everyone 24/7.
  • Hahaha. This exactly. Google Nexus 6P
  • Personal Info? Newsflash!! Nobody gives a **** that you have a missed call or received a text message. What's more...even if the screen did show personal info and there were people out there who gave a ****...it's a limited number of pixels at around 10-20% brightness and therefore impossible to see at distance. Don't knock what you clearly have no experience of. Posted via the Android Central App
  • Clearly have no experience? I've owned the Nexus 6, Galaxy S2 (which had that app that would display notifications on the screen), and a Moto X. Yuck. It was awful. Especially when my Nexus 6 would be sitting in the seat next to me in the car (I did try to use the active display junk for a while) and it would turn on every bump in the road thinking I was picking it up. Distracting the driver (me) and wasting battery. Noooope.
  • The Moto X implementation was better. Because it uses sensors to detect the wave of a hand to turn on the display. A small loan of a broken G4
  • No Android phone has done it right to-date to my knowledge (and I include the Moto X in that - of which I was a fan) Do me a favour and look at how Nokia did it (they even managed successful implementation of Glance on an LCD with the Lumia 920) If you still think you'd be distracted...you probably shouldn't be driving! ...... Look...there's a squirrel!! Posted via the Android Central App
  • Nothing wrong the Motorola's implementation. It was better than the Nokia's IMO since you could see just a little bit of extra info BUT you had to hold the app's icon for that, which meant it was hidden from others' prying eyes lol
  • Nexus's implementation is that it replicates your lock screen notifications which is why the private info is visible.
    Motorola's implementation was precise and it also showed just the icon for the app for which you got the notification. To get the extra info, you had to hold the icon
  • It will stop to show a real light screen in my dark pocket for ever!! Thanks from the battery side. Posted via the Android Central App
  • If it's implemented correctly, it will not be ON in your pocket or when the phone is face-down, since it checks for the same via the proximity sensor.
  • You may wanna hide your email address. Your screenshot shows your email address "....hero@gmail.com"