Category: Applications sobriety

Will upgrading to Android 6 improve your battery life?

Posted on by Thomas CORVAISIER
Reading Time: 4 minutes

There has been a lot of noise recently about Android’s newest version 8 “Oreo”. However, a lot of people out there are still using older versions, and may be wondering if the new versions are worth the upgrade. I’ve been confronted with this choice on my Fairphone2 running Android 5.1. Should I upgrade it to Android 6 Marshmallow? Google claims that Android 6 will get you more battery life. Let’s check that, shall we!

Never install an update without first checking that you actually need it

You know how people can heavily rely on their smartphone nowadays. I’m no exception to that. I’ve been intensively using my Fairphone2 for over a year now, and I must say that I’m pretty happy with it. Except for the very few occasional crashes (but no more than on my previous device), it has become my trusted everyday companion.

When I got it, it shipped with Android 5.1 (Lollipop). The Fairphone team is doing its job properly and a few months later, they proposed an upgrade to Android 6 (Marshmallow).

But Hey, come on… I’ve been in the IT business for quite a while now, and an IT user for even longer (my first OS had a blue background). As much as I love getting the latest version of pretty much anything, I’ve developed a healthy habit: never install an update without first checking that I really need it.

What about this battery consumption claim?

Part of this habit is based upon the «if it ain’t broke, don’t fix it» approach, and the other part is defiance. OK, this update will bring nice features, and maybe I will actually need some of them. But what would be the cost of it? Will this update increase the footprint of the software (bigger memory? disk size? CPU needs? And what about battery consumption?…).

I had already checked the novelties included in Android 6 and decided that none of those were interesting enough for me to jump in. However there was still one interesting claim: Android 6 was supposed to lower the battery consumption of the OS, thus allowing longer battery life.
So, prior to upgrading, I needed to know if this claim was true.

Let’s look into this

This is where working for a company which specialty is metering battery consumption of mobile devices comes in handy. Folks in the office next door spontaneously developed an energy probe for the Fairphone2 after I threatened to join the company choir, and they even let me play with a crude but simple version of a battery monitoring app. (Before you ask: no, this is not available for sale (yet), it’s only an internal lab thing. For now.)

So, during a few days, I was able to monitor the battery consumption of my Fairphone2 when making Phone Calls, when using the apps I use on a daily basis, and also some others just for the experiment: K9-Mail, Twitter, Meteo France (France’s official weather app), and I tossed in a few games on Hearthstone (“work hard, play hard” they say) and listened to the FM Radio through the built-in antenna and app, and through some randomly picked internet Radio App.

I started by measuring under Android 5.1. Then I upgraded the OS to Android 6, and did a second run of measures. Please note that the applications have not been upgraded in the process: we’re talking OS only here.

These measures have led me to some interesting findings. I’ve been able to check whether Marshmallow really lowers battery consumption or not, and I also got some insights about individual applications behavior.

Rankings my everyday apps

The first set of measures I ran under Android 5.1 led to these findings.

All values are given in µAh/s. These are “microAmpere.hour per second”. As the Fairphone2 has a battery capacity of 2,400 mAh, this means an app with a discharge rate of 300 µah/s will drain the battery in a little more than 2 hours.

• The discharge speed for my use cases vary in range 146 to 305 µAh/s
• Some notable values:

  • Hearthstone : 305
  • Twitter : 247
  • Phone call : 191
  • Radio (built-in FM): 160
  • Idle (doing nothing but not in sleep mode, screen is on): around 150

The full list of tests cases is as seen on the graph.

Casual findings: about Twitter and FM radio

By looking at these values, we get some unexpected insights:

  • Twitter with the Night Mode on doesn’t save any energy over Twitter with the default white background: OK, this is consistent with the Fairphone2 screen technology – read more about this)
  • Listening to the radio through built-in FM consumes 20% less battery than a random internet Radio app. Of course you only get your local stations, but depending on what you want to listen to, you are better off using this built-in FM.

Is Android 6 improving my battery life?

Well, it’s time to answer this question. Let’s upgrade the phone and run these measures again. Now here is what we get:
• Average discharge speed varies in range 102 to 313 µah/s
• Some notable values:

  • Hearthstone : 313
  • Twitter : 208
  • Phone call : 163
  • Radio (built-in FM) : 143
  • Idle : 102 to 134

I had a look at the other metrics: it seems like the processor is better managed. We get around 9% less CPU used by the system when the phone is idle. CPU-intensive apps also have better performances: I get a test score of 1,058 at 3DMark Slingshot with Android 6, vs 912 with Android 5.1) but this happens at the cost of an increase in energy consumption: +10% discharge rate for 3DMark.

Conclusion

In most cases, Android 6 brings a significant energy gain: around 5% to 15%. Beware though when using CPU-intensive apps, you’ll get better performances but at the cost of more battery consumption from these apps.

So, will I keep Marshmallow on my device? Yes.

Is Twitter Lite really that light for your battery life?

Posted on by Olivier PHILIPPOT
Reading Time: 5 minutes

Earlier this spring, Twitter launched Twitter Lite, which is, as the name suggests, a lighter alternative to its mobile application.

We have seen a lot of users wondering if Twitter Lite was really honoring its promises: is it really that Lite? Does it actually consume less data? Does it lower the impact on the smartphone’s battery for real?

Since GREENSPECTOR provides a benchmarking software and a way to quantify energy consumption of mobile and web applications, we wanted to find out by ourselves.
So today we are going to benchmark Twitter Lite and see how it compares with its older sister, the native mobile application.

Introduction of the challengers

A word on PWA (Progressive Web Applications)

We said earlier that Twitter Lite was a Progressive Web Application, but what is it exactly?

On the blog, we previously talked about hybrid mobile applications in our analysis of the memory cost of a Cordova Application, which are half-native applications in the sense they are traditional web applications running through a web-view in a native container.

PWA doesn’t work exactly the same way, they are a new kind of mobile web applications which aims at being light, fast and reliable across poor network conditions. They run through your web browser (Google Chrome at the moment) just like normal webapps, so you don’t have to install anything else.
They follow a set of standardized practices using the latest web standards and technologies such as offline storage, the push notification API and service workers to provide an experience as close as possible to “real” applications.

Google provides a tool called Lighthouse for auditing performance metrics and best practices of PWA. You can check out the Lighthouse metrics evolution of Twitter Lite since it has launched.

Benchmarking methodology

Tools

To collect all the data we needed, we made use of a Google Nexus 5 running Android 5 Lollipop installed in the GREENSPECTOR Power Test Cloud. The Power Test Cloud is an automated platform we built to benchmark mobile and web applications on real devices, in the cloud, following the test cases we have standardized:

  • Reference -> measure the resources consumption without any application
  • Application Launch -> measure the resources consumption while application is launching
  • Application Idle in foreground -> measure the resources consumption while application is idle in the foreground
  • Application Idle in background -> measure the resources consumption while application is idle and put in the background

Measurement conditions:

We measured each of the previous test cases under different settings which are noted as follow:

Twitter application for Android (v7.22.0):

  • Twitter app with stock settings -> Twitter
  • Twitter app with ‘lite like’ settings (disabling images/videos preview etc) -> Twitter_datasaver

Twitter Lite:

  • Twitter Lite with stock settings -> TwitterLite
  • Twitter Lite with Data Saver -> TwitterLite_datasaver

Each test case have been run with these configurations at least five times in order to have stable and reliable measures.
The battery was charged between 30% and 80% of its full capacity and all unnecessary services – such as Bluetooth, GPS, Speach recognition (aka “OK Google”), etc – have been deactivated, reducing as much as possible the noise in the results.

Measures, FIGHT!

First Round: Twitter vs Twitter Lite (stock settings)

Overall results

This one-on-one shows interesting results. Twitter Lite PWA seems to consume around 10% less battery power than its native equivalent. On the other hand, the results show an increase of 116MB on memory consumption and another increase of 4000% on network activity. Let’s dive into the details to better understand where this difference comes from.

Loading

First thing first, let’s check out the results of the loading step:

As we can see Twitter Lite consumes 480KB more data than the Twitter native application. This makes sense, in this case, the Google Chrome browser that hosts the PWA needs to load all of the application’s code and logic, then load the timeline. With the native application you only need to load the timeline’s data.

Idle

Looking at the idle step while the app is in the foreground (background step results are not considered here, we have no comparison point on the PWA) confirms what we just saw. Twitter Lite shows a data consumption which is a bit higher but pretty equivalent to the native app one. If we look at the energy side, the PWA has a slightly higher consumption (around 12% more) than the mobile application.

Second round: Twitter vs Twitter Lite (data saver settings)

Loading

On data saver settings, we observe a gain of around 50% on the amount of data transferred during the application’s loading step in each case. Still, Twitter Lite resources consumption is far above the Twitter application.
Moreover, the Lite version drains almost twice as much battery capacity during this step than the native application.

Idle

Here, we observe the same behaviors as earlier. The Lite application consumes more energy than the native one, almost 25%, and twice as much data on idle step.

Conclusion

Twitter Lite ambition was to be light and, thus, help reduce resources consumption, mainly bandwidth, but we could have assumed it would have had a benefit on the battery life too.
As we’ve seen through measures and comparison, it consumes more resources and energy than its native counterpart in all scenario we’ve tested. The only benefit of using the Lite version is not to have to install an application on your phone. The mobile application wins this game, however it does not mean that the PWA is not lite, it is, the numbers are not that high afterall, it only means it is not lighter.

Should you switch your wallpaper to affect less the battery life of your smartphone?

Posted on by Olivier PHILIPPOT
Reading Time: 6 minutes

Colors influencing power consumption of smartphones and tablets is a debate that never gets old. We hear a lot of preremptory assertions (like «pick a black wallpaper to consume less») which, most of the time, don’t take into account underlying technologies – though they are very diverse – or specific studies about the topic. So, as per usual, as a mobile-device-energy-measurement freak, I wanted to know more.

Why conducting this study?

Decreasing power consumption of mobile devices is a leitmotiv for all manufacturers. Indeed,battery life is one of the main criteria considered before buying a device. Manufacturers are working towards component optimization: improvement of processors efficiency, sensors technologies consuming less, increase in battery life capacity, etc. When I implemented the methodology for measurement of software power consumption at GREENSPECTOR, I had to go through and study every setting that could possibly influence this consumption. Yes, screens are part of it, but it seemed interesting to dig deeper the topic. Let’s have a look, shall we!

Testing Method

In order to measure energy behaviors of screens, I have created a series of tests making the screen brightness vary according to a rate (0%, 25%, 50%, 75% et 100%) and displaying a whole page in a specific color (Red, Green, Blue, Black, White). Then, I ran the tests on the different mobiles from our Power Test Cloud. Power consumptions (and other resources) are measured with GREENSPECTOR probes, installed on the devices. Finally, I get the measurement results back and I’m able to make cute graphs and can more easily interpret them.

First couple measures on a Nexus 6

I use my personal favorite device to begin with, the Motorola Nexus 6, which screen uses the AMOLED technology. We get the following cartography and consumptions: in abscissa are the different displayed colors, in depth is the brightness variation and on the ordinate axis we have the resulting battery life consumption:

First conclusions

  • Consumption is lower for Black. I’m pretty glad, this confirms other studies such as this one or this one, and this is also what we theoretically expect from the AMOLED technology.
  • The difference in consumption between colors is low when brightness is down. This seems intuitive but measures confirm it.
  • Consumption is incremental in the following order: Black < Green < Red < White < Blue
  • Diffferences can be very distinct: with maximum brightness, blue consumes 78% more energy than black (hence, a blue screen with a 100% brightness will empty the battery in 5h30, whereas a black screen with the same brightness will do it in 12h!).

Explanations

Nexus 6 is based on an AMOLED technology: Active-Matrix Organic Light-Emitting Diode. This technology connects the OLED technology (organic light-emitting diode) and active matrices (each pixel is commanded independently). It is an alternative to the historical LCD technology (Liquid Crystals displays).

Black is easy to display on AMOLED screens as pixels just need to be turned off. This is the reason why Black consumes less. White is a mix of Blue, Red and Green, we can find it on the average.

Measurement on a Samsung Galaxy S6

To be able to confirm this trend, I measured the Galaxy S6 energy behavior, exploiting a derived technology called Super AMOLED:

We can observe the same behavior with a slight difference: this time, white consumes the most (44% more than Black), just before Blue. Overall, observations are the same: Black is much less consuming, and White and Blue consume more than other colors.

Measurement on a Nexus 5

For AMOLED, it is obvious. But what about other technologies? Let’s take the example of the Nexus 5 for instance, with the LCD IPS+ technology:

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We can clearly see that with a LCD IPS+ screen, color doesn’t influence consumption. However, we can note that, with maximal brightness, White will consume just a bit more (4% gap, a 10 or 15 mn difference on the theoretical battery life).

IPS technology (In-Plane Switching) is a LCD technology. IPS+ adds LED to improve display. In LCD screens, theory is that consumption is independent from color: it’s all good then! By the way, let’s note that Retina technology of Apple products used to rely, up to now, on an IPS technology, but it seems like things are about to change with the new iPhone 8s with an OLED screen: iOS app designers, remember that.

Measurement on a Nexus 9

Measurement on a Nexus 9 tablet, based as well on an IPS technology, provides the following results:

Observations are similar to the Nexus 5 ones, with barely a 2% difference between colors.

Measurement on Pixel C

When measuring on the Google Pixel C tablet, a recent model with a LCD technology in the LTPS version, we get the following:

There is always an overall dependence of battery life consumption towards color. However, a color behaves a bit differently: with a maximum brightness, the White impact is 12% bigger than the Black (9h autonomy for Black versus 8h in White).

LCD LTPS (Low Temperature Poly-Silicon) is actually a Thin Film Transistor Technology (TFT) with an active matrices technology (like AMOLED). Differences on Whites probably comes from the possibility we have to whether or not turn on pixels.

Comparison for the user

Now we executed these tests, let’s try and compare these different models between each other. To do that, we take the consumption induced by the display of a black or white screen, and divide it by the screen size. When talking size, we don’t take into account the surface (which would be scientifically more correct), but simply the diagonal in inches, as it is the only information the user has access to: this is the one that matters when making a decision.

Based on an AMOLED technology, the Galaxy S6 has a rather high consumption. Same for the Pixel C with the LTPS IPS technology (with an incremental increase of consumption as brightness goes up). In Whites, no particular technology stands out. However, this analysis is to be considered cautiously as we didn’t measure a lot of devices.

By observing how Black behaves, we witness the whole point of the AMOLED technology which consumption is linear. One thing though, with minimum brightness (0%), consumption is more important than with other technologies. On the 25% – 50% range, there is no difference; and benefit is obvious for high brightness, for which AMOLED is the best suited.

Conclusion

Here comes the time to deliver our final verdict… Should you choose a black wallpaper for your smartphone or tablet?

Users

If you have an AMOLED screen: yes! No doubt here, pick your wallpaper picture predominantly black. (To find out what type of screen you have, look up characteristics on the manufacturer’s website or on sites dedicated to that matter). If your device is based on a different technology, you can always apply this best-practice, but battery life gains will be less important.

With the same reasoning, favor applications with black skins or interfaces (like Google Black for instance, or Twitter « night mode » …). And if your favorite app doesn’t offer a « dark » version, ask the editor!

To everyone: set brightness to the minimum required to still have a good user experience. Around 25%, current technologies allow to get a rather good rendering in most cases. Avoid to set at 100% permanently – it is usually the value I use outdoor on sunny days.

If you have the feature on your phone, activate the automatic brightness adaptation. Verify that it isn’t set too high, or a manual setting could be more efficient.

Profesionals with a company fleet

As per usual, settings and screen designs are under control, it is possible to pick the smartphone the most suitable to the actual use. Don’t rely only on manufacturers data, you can conduct specific tests that will give you better and clearer information on real battery life. Specify interfaces adapted to the phones. If you have a fleet with AMOLED screens, it is better to have darker interfaces rather than light ones to preserve the battery life of the devices in your fleet.

Designers

Color choice mainly depends on graphical charter and brand but energy consumption can be an additional criteria making your design furthermore efficient. It is interesting to ideally specify two themes: a dark one and a grey one. This would allow the user to pick the theme the most-adapted to its device.

Developers

In order to adapt design to hardware context, it is interesting to offer the user the choice of a darker theme. A screen modification option should be implmented (easy with CMS, more complicated with a framework).

Does Facebook lite save your smartphone battery ?

Posted on by Abdelmounaïm BELGHALEM
Reading Time: 4 minutes

Today (28th February 2017), is the International No Facebook Day. Is Facebook application really a “bloatware”? Is Facebook Lite lighter? Does Facebook lite save your smartphone battery ?

Continue reading “Does Facebook lite save your smartphone battery ?”