A First Inside Look at Pokémon GO Battery Drain. You won’t catch many, if your battery dies so quickly.

Ever since its public release in Australia, New Zealand, and United States, Pokémon Go, the augmented reality mobile game from Nintendo and Niantic Labs, has quickly captured the fascination of the app world. Within one week, it became the Number 5 most popular app among US Android daily app users.

The location-based augmented reality (AR) game brings AR experience — interacting with pokémon in the real world — by using almost all of the power-hungry components of a typical smartphone: camera and sensors, GPS, Screen, CPU, GPU, and network radios. As such, it has also become one of the most battery-constrained apps among the 2 million or so apps in the consumer app marketplace.

In this following, we report on the first in-depth study of how battery is drained by Pokémon GO using the proprietary energy drain diagnostic tools from Mobile Enerlytics. Our study answers questions concerned by the the millions of pokemon GO fans and gives insights that assist pokemon GO developers on how to go about cutting down its battery drain.

  1. How long will my battery last for common play scenarios?
  2. How long will the recommended battery saving techniques extend my battery life?
  3. Which phone components consume most of the battery?

We used a Nexus 6 phone for all the experiments. Its battery capacity is 2400mAH. We installed pokemon GO version 0.33.0, as well as our battery drain diagnostic tool. Screen brightness was kept 30% of the maximum level 255. A Pokemon GO fan then interacted with the app using WiFi on a university campus with good WiFi coverage, while its battery drain information is being collected and analyzed.

1. How long will my battery last for common play scenarios?

Like any sophisticated app, Pokémon GO comes with many possible play scenarios a fan can be engaged in. For starters, we tested four common scenarios the app can be in: Idle, Walk, Collect Pokeball, and Capture Pokemon.

Figure 1 shows how long a fully charged battery will last if the app stays in each of the four scenarios, without turning on the two battery saving options: battery saving mode is off, and AR mode is on.

Figure 1: Battery life when Pokemon GO stays in each of the 4 scenarios.

We see that Capture Pokemon is the most battery intensive scenario, depleting the battery in just 1.95 hours. The scenario uses augmented reality to show pokemon characters on the camera screen. In addition, the user needs to throw Poké balls from screen bottom to capture the Pokemon. This involves all of the phone’s power hungry components like camera, CPU, GPU and screen. Other scenarios do not use camera which cuts down their battery need. We do not observe much battery drain difference between idle (stationary) and walk scenario. The reason could be that the avatar changes position within the game’s map often even when the phone is stationary.

2. How effective are the recommended battery saving techniques?

The Pokemon GO developers anticipated the battery as a major roadblock to the overall user experience, and built into the app two battery saving configuration options: battery saving mode and AR off mode. The battery saving mode is designed to save screen energy while walking, by dimming the screen and slowing the refresh rate, if the user points the top of the phone towards the ground, a natural holding position while walking.

The AR off mode is designed to cut the app’s camera battery drain, another major source of the app’s battery drain. When the AR mode is off, the camera will not open up when it is time to capture a Pokémon, and the user loses the AR experience of having her actual surroundings just behind the pokemon.

We analyzed the effectiveness of the two options on the game’s battery drain for Walk and Capture Pokemon scenarios. Figure 2 shows how long the battery will last if the app stays in walk, with the battery saving mode on or off, under several screen brightness levels. We see that the battery saving mode extends the battery life by 23% , 30%, and 40% for brightness levels 30%, 50%, and 80%, respectively.

Figure 2: Life of a fully charged battery when Pokemon GO stays in Walk.

Figure 3: Life of a fully charged battery when Pokemon GO stays in Capture Pokemon.

Figure 3 shows how long the battery will last if the app stays in Capture Pokemon, with AR mode on and off, under screen brightness level 30%. We see that disabling AR mode nearly doubles the battery life.

3. Which phone components consume most of the battery?

Figure 4: Component power draw breakdown for Capture Pokemon Scenario

Figure 5: Component power draw breakdown for Walk Scenario

To gain insight into how Pokemon GO drains the battery, we used our tool to break down its total battery drain into portions from engaging different phone components needed to delivery the overall user experience. Figure 4 shows the total battery drain and breakdown of the game under AR on and AR off for a 2-minute play of Capturing Pokemon (throwing a ball every 10 seconds). To make it easier to relate the energy drain with the component power draw, we show battery drain (and breakdown) in terms of average power over the app play duration. Figure 5 shows the total battery drain and breakdown of the game under normal mode and battery saver mode for a 2-minute play of Walk. We see that

(1) The major battery saving for battery saving mode comes from Screen (19%) and for AR off mode comes from Camera (56%);

(2) GPS drains only about 4–7% of the total app energy;

(3) Interestingly, the app drains little battery doing networking (~5 mA), as it performs infrequent networking of fairly low volume data (about 7 KBytes every 30 seconds for the Idle scenario.)

(4) And though there is no augmented reality in AR Off mode, GPU actually drains 3X more battery (~150 mA) than in AR On mode (~49 mA).

Figure 6: Timeline of Component-wise power draw in Capture Pokemon.

To understand the above GPU power behavior and gain further insight on Pokemon GO’s battery drain behavior over time, we used our tool to show the timeline of the power draw by different components while the game was in Pokemon Capture with AR On mode and AR Off mode, and the user threw a ball towards pokemon every 10 seconds. We see that

(1) For both AR On and AR Off, Screen and GPS are turned on all the time, drawing steady power, while Camera is on only for AR On mode;

(2) Surprisingly, for AR On, GPU and CPU power draw is high initially but both gradually decreases significantly around 35 second CPU with GPU power almost becoming zero! The likely reason is that when AR mode screen just started, CPU and GPU were engaged actively to instantiate the 3D animated objects (such as Ball, Pokemon) on camera screen. Afterwards, the only major task left was to compute the coordinates using motion and position sensors (e.g accelerometers, gyroscopes) to correctly position the already instantiated 3D objects on the camera screen.

(3) For AR Off mode, although the green background is static, there are regular changes on screen such as the shade of pokemon which results in continuous use of GPU and CPU.

(4) We did not include the power consumption by sensors used in app as they are insignificant. For example, Gyroscope consumes 1.5 mA and Accelerometer consumes 1.3 mA.

Conclusion

In summary, our analysis has shown that the AR experience of Pokemon Go comes at a hefty toll on the battery — draining battery almost twice as fast compared to AR off when capturing Pokemons. We expected battery saver mode to take close to zero power, but it only reduced battery drain rate by just 19%. Pokemon Go drains fully charged phone battery in as little as 2 to 4 hours on a high-end phone (Nexus 6) making it one of the most battery-hungry apps ever.

Our patented app battery management (ABM) solution, Eagle, demonstrated that CPU and GPU are the biggest consumers of battery in almost all scenarios and should be optimised first by the Pokemon app developers; camera and screen are power hungry components and users should keep them off longer with AR off and battery saver mode on to extend their battery life by 2x and 19% respectively. 

Music Lovers: Switch Streaming Music Apps and Extend Your Battery Life by 2X

Since Pandora first launched music streaming 15 years ago, the music streaming category of mobile apps has become crowded with over a dozen popular alternatives today, many of which are undergoing rapid revisions. For example, Spotify releases a new version of its mobile app every two weeks. As a result, deciding on which music service to choose has become often difficult. In fact, a simple Google search for “Pandora vs. Spotify” today churns out over 4 million search results, which attempted direct comparisons of leading music streaming services along a multitude of dimensions, such as song selections, features, user experience, and business model.

Since battery drain is an important factor that affects user experience, we carried out a head-to-head comparison of the battery drain rate of 3 leading streaming music apps.

To isolate the impact of other apps running on the devices, we tested the battery draining rate of the recent versions of Pandora, Spotify and Google Play Music in the lab.

Screen Shot 2015-12-21 at 9.47.15 PM Our methodology for the test consists of three steps. In step 1, we measured the battery life in playing music in foreground and background, respectively. We uninstalled all the other third party apps from a Nexus 6 phone so that no other background task was running. We then put each of the three music apps in the streaming music mode to play music from a pre-selected music categories, under WiFi (see sidebar for details). We measured how long it takes to drain the entire battery for each app. The results are shown in the following graphs.

 

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In Step 2, we measured how much time real users spend playing music in foreground and in background using their smartphones. The analytics from Eagle of 15,000 Android users who have installed at least one of the three music apps above shows that 83% of the total music app usage is spent on playing music in the background. On average, users spend 10 minutes playing music in foreground and 49 minutes playing music in background per day.

Finally in Step 3, we calculated the expected battery life in playing music under typical user behavior, as the weighted average battery life of the above measured battery life when playing music in foreground and in background,  weighted by the percentage foreground (17%) and background (83%) playing time measured on the 15,000 Android phones.

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The results, shown above, show that Google Play Music drains over 2X less battery compared to Spotify, and Pandora drains 70% less battery than Spotify. In other words, for a music fan who spends a lot of time playing music on her smartphone, switching from Spotify to Google Play Music can extend the battery life and hence listening time by 2X!

We plan to benchmark the battery performance of other streaming music apps and we also welcome streaming music app vendors to repeat these experiments on different handsets following the above simple methodology.

Are pre-installed apps more power hungry?

Carriers as well as handset manufacturers pre-install several apps on mobile devices that they sell. In this post, we exhaustively study pre-installed apps by leveraging the rich energy profile information that Eagle provides — our analysis below is based on data collected from 70K+ devices. One primary concern that users have about pre-installed apps, which leads them to be used less often, is about their battery usage being high. This concern gets magnified given that users quite often can’t delete these apps unless they root their phones, etc. In sharp contrast to this preconceived notion, we show that pre-installed apps actually have similar power draw as apps with similar functionality from the Google Play store. Our conclusion: power usage of these pre-installed apps is not worth losing sleep over!

Our battery management app, Eagle, has a patented technology to accurately keep track of both the time and energy spent inside each app. For this study, we analyzed data collected by Eagle from three different Android device manufacturers: Samsung, HTC and Motorola.

We first averaged apps we see across all the users of Eagle and compared the number of pre-installed apps that users have on average compared to the total number of apps. Amongst the three most popular Android device manufacturers, Samsung phones have the highest percentage of pre-installed apps (25.6%) followed by HTC (23.3%) and Motorola (12%) (see Figure 1).

Figure 1: Number of pre-installed vs. total apps across device manufacturers.

The Table below shows the average daily usage across the different device manufacturers, with Samsung devices being used the least (88 mins. per day) compared to Motorola and HTC. In terms of usage across different pre-installed apps, Samsung devices have the least usage at ~6 mins per day compared to 12.6 mins per day for HTC devices.

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The next question we ask is how often are pre-installed apps actually used compared to apps that users install directly from the app stores (see Figure 3). Interestingly, HTC phones have the highest usage of pre-installed apps at 12% of total daily usage across all apps. Samsung is second at 7% followed by Motorola at 6%. Next, looking at the breakdown in time spent across the variety of pre-installed apps for these manufacturers (see Table above), a few other notable trends emerge: The pre-installed Browser on Samsung and HTC phones is used for about 2 minutes per day whereas Motorola users use the pre-installed browser very infrequently. However, given that Samsung devices are used less often on a daily basis, hence, we next compare each pre-installed app’s usage in terms of percent time spent across all pre-installed apps (see Figure 4). In terms of Camera apps, Samsung and Motorola phones seem to have a popular pre-installed Camera app whereas the pre-installed Camera app on HTC devices seem less popular. For Motorola devices, the most popular pre-installed app is a Gallery app at 50% usage. Samsung devices also have a non-trivial usage of the Gallery app at 17% across all pre-installed apps.

Figure 3: App usage on Samsung, HTC and Motorola devices.

Figure 4: App usage across pre-installed apps on Samsung, HTC and Motorola devices.

The low usage of pre-installed apps compared to user installed apps should come as no surprise, as they were not actively downloaded by the user to serve a specific need — hence user may sometimes be not even aware of them. Moreover, several myths prevail about pre-installed apps: (1) overall they draw more power, (2) and they draw a lot of power in the background, i.e. even when they are not used — yet they can not be deleted easily.

In Figure 6, we compare the foreground power drawn by the six most popular user-installed apps versus the six most popular pre-installed apps. We see they are remarkably similar, suggesting that pre-installed apps should not be discriminated in terms of power efficiency!

Figure 5: Average foreground power (mA) for user-installed and pre-installed apps on Samsung devices.

Next, we pick groups of pre-installed and user-installed apps with identical functionality, e.g. Samsung Clock and Android clock, and perform a head-on comparison within each group. The first set consists of five such groups of Samsung pre-installed apps versus user-installed apps. Figure 7 shows the power draw of the two competitors within each group is largely a wash — there is no clear winner or loser. This further validates our previous finding that pre-installed apps are not drawing more power than their user-installed counterparts.

Figure 6: Foreground power between pre-installed samsung apps and user-installed apps on Samsung devices.

So far, the pre-installed apps seem to be vindicated as not being overall “power hungry” when they run in the foreground. But in the background — do they consume more power? To answer this, we analyzed the “background” power usage of a few of the most popular pre-installed apps and user-installed apps on 8K devices. Figure 8 below shows a scatter plot for these apps as the average daily background power over the app’s average daily usage time. Amongst the user-installed apps as well there is no clear trend as there are apps that draw more power in the background (e.g., Facebook Messenger) and those that do not (e.g., Facebook). Moreover, on comparing two different browsers: Chrome which is user-installed and Samsung Browser which comes pre-installed, we find that they are quite similar in terms of background power usage. Samsung Video Player when compared to YouTube draws more power though and hence it appears that there may be room for power-improvement in Samsung Video Player. Hence, background usage corroborates what we found about foreground usage earlier — that pre-installed apps seem to be consuming as much power on the average as their user-installed counterparts.

Figure 7: Background power draw of a few apps compared to their daily usage on Samsung devices.

So far, we’ve focused only on pre-installed apps as installed by device manufacturers: What about pre-installed apps as provided by carriers? Are those more or less power-hungry? Figure 9 below, groups similar apps by functionality, while including a user-installed app, an AT&T pre-installed app and a Verizon pre-installed app in each group. Once again, based on the data below, we can’t argue that Verizon or AT&T pre-installed apps are more or less power hungry!

Figure 8: Foreground power usage of groups of apps with similar functionality while comparing user-installed, AT&T and Verizon apps per group, on Samsung devices.

Conclusion: In this article, we’d set out to examine whether pre-installed apps are indeed consuming more power than their user-installed counterparts. Contrary to preconceived notions about pre-installed apps, they actually do not consume any more power in either the foreground or the background. Hence, our recommendation to smartphone users: if battery usage is your concern, there’s no need to root your device to delete the pre-installed apps.

An Inconvenient Truth about Mobile

How often do users charge their smartphones? Are mobile phones mobile enough to hold charge for a day? How does short battery life affect user behaviour and user experience?
We answer these questions via the following infographic generated by analysing data collected by Mobile Enerlytics from 37k Android users across 100+ countries.

All the data logged by Mobile Enerlytics is strictly anonymised; we don’t collect any information that may identify individual users.

Breakdown of users using external battery backup is obtained from here.

Mobile Enerlytics logs remaining battery percentage and phone charger connect/disconnect events; we use these event timings to generate charging and blackout related insights. The phone usage is defined as the ratio of screen-on time over wall-clock time.

Mobile Music

What are the music listening patterns of smartphone users? Which music streaming app drains the least amount of phone battery? The following infographic shows the answers from analysing data collected by Mobile Enerlytics from 37k Android users across 100+ countries.

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