Battery Life

Battery life is important beyond any doubt. No one wants a tablet or phone that can only spend three hours away from a charger before it dies, no matter how good the device is. While such battery life might be incredible for a desktop replacement or anything else that realistically spends most of its life plugged into a charger, mobile devices are usually carried on the go and used far away from a charger for significant amounts of time. Probably the ultimate example of this is travel, where one might use a tablet to watch movies and browse the internet for a few hours over the course of a flight.

As a result, a significant portion of our reviewing efforts are devoted to determining battery life. In order to quantify battery life, there are inevitably a lot of test cases to cover. Some people might spend most of their time in an e-reader app, others might spend most of their time playing games or similarly intensive tasks on their phones. There’s no real standard for usage, so a tablet that might last a day for one person could last a week. As a result, the goal of our testing is to provide a useful relative comparison. In order to do this, we attempt to equalize for variables like display brightness by setting all displays to 200 nits for battery life testing. Due to the inability to completely eliminate the variables that come with live network testing, we also use strong network reception with high throughput on LTE to ensure that things like power amplifiers are either at a low power setting or bypassed entirely.

Web Browsing Battery Life (WiFi)

Our first test is the venerable web browsing test, in which we load a selection of web pages from full charge until the device shuts off from lack of battery charge. In WiFi battery life is pretty much identical to the iPad Air 2, which might be surprising given that the battery is only 41% larger. That might sound like a lot, but the display of the iPad Pro is 77% larger at the same 264 PPI pixel density, which means that there’s a pretty sizeable efficiency gap between the iPad Air 2 and iPad Pro. The improved display and SoC are likely to be the main reasons for this, as the 20nm SoC process that was used to make the A8 SoC was quite leaky due to its traditional planar transistor structure compared to the FinFET process used in the A9X.

Web Browsing Battery Life (4G LTE)

Interestingly, for whatever reason when re-running the same test on LTE battery life is noticeably different when compared to the iPad Air 2, where LTE and WiFi battery life were relatively close. I suspect that RF power is pretty similar between the two devices, but due to efficiency improvements on the display/SoC side the difference in battery life due to additional RF power consumption is magnified.

Video Playback Battery Life (720p, 4Mbps HP H.264)

The more interesting test result that I encountered over the course of battery life testing was our tablet video rundown test. For whatever reason, web browsing clearly lasts a decent amount longer. It's pretty unlikely that the web browser has a lower SoC load when video is basically entirely dependent upon fixed function hardware decode. The most plausible explanation here for me is that we're seeing differences that arise from panel self-refresh, which can kick in on our web browsing test while the same definitely doesn't hold for our video test, which basically requires at least 30 FPS refresh rate continuously for the entire duration of the test. Overall that this makes the iPad Pro worse for content consumption, given Apple's content creation goals, is an unexpected turn of events.

BaseMark OS II Battery Life

Moving on to the more SoC-bound tasks, we can start by looking at Basemark OS II, which is basically a CPU power virus that can be used to examine the upper bound for device TDP, in addition to nominal sustained CPU load. It’s evident from this test and some back of the envelope calculation that total device TDP excluding display power is roughly 5W, which is about right given the size of the device. This suggests that the A9X can be directly compared to Intel’s Core M in both performance and power, for better or for worse. Performance here is good, with relatively low throttling due to the use of a FinFET process and solid implementation of the Twister architecture.

GFXBench 3.0 Performance Degradation

GFXBench 3.0 Battery Life

In our GPU throttling test, the A9X has effectively made it impossible to actually use T-Rex as a throttling test as it’s essentially pegged at vsync for the entire duration of the test. The iPad Pro also lasts a similar amount of time here as on the Basemark OS II test, which suggests that this test is still reaching TDP limits for the GPU, even if it doesn't manifest in the form of reduced performance.

Charge Time

While battery life is important, any time you’re dealing with a mobile device the time it takes to charge the battery is important as well. The usual example here is travel, but simply forgetting to plug in a device overnight can show the importance of charge rate. In the case of the iPad Pro, Apple ships it with their usual 12W charger. One might be tempted to suggest that the battery would be charged in about 3.5 hours, but it’s necessary to get the data and avoid speculation on something like this. In order to test how quickly the iPad Pro charges, we measure the difference in time between first plugging in a fully discharged tablet and when the charge is complete based upon power draw at the AC adapter.

Charge Time

Interestingly, the iPad Pro takes a pretty significant amount of time to charge, at over a full hour longer than the iPad Air 2. While some might be okay with this, it’s definitely a sore spot for the iPad Pro as a higher voltage charger would be able to charge the device at a more acceptable rate. I’m not really sure why Apple decided to go this route, but there’s really no clear solution here unlike the case of the iPhone 6s Plus. The charger also definitely isn’t enough to ensure that you’re always charging the iPad Pro while in use either if the SoC is in overdrive/turbo states as thermally constrained power draw is already around 9-10W.

Despite the long charge time, overall the iPad Pro is quite mobile. However, it does regress somewhat relative to the iPad Air 2 due to its longer charge time, even if battery life is equivalent. Depending upon your use case though it might be difficult, if not impossible to tell the difference.

System Performance Cont'd and NAND Performance Display
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  • ddriver - Saturday, January 23, 2016 - link

    So in your expert opinion, all programs do is syscalls? No application logic, no application data? LOL

    Also, API calls are NOT syscalls. Syscalls are requests to OS kernel, API calls are just regular calls to a library. Fundamentally different things.
  • FunBunny2 - Saturday, January 23, 2016 - link

    -- Fundamentally different things.

    exactly the same: your not writing active code, but calling out to somebody else's code to do the work. in neither case does it matter what you're source language is, from a performance point of view. there's a reason that java mostly beats C++ these days.
  • Constructor - Saturday, January 23, 2016 - link

    The main reason for that is the "well, it's fast enough, and if not we'll compensate with CPU upgrades" mentality in many projects.
  • gistya - Sunday, January 24, 2016 - link

    Why are we talking about Java and C++ here? Just curious.

    I recently worked on Google's j2objc project and it's pretty freaking slick. You can translate Java code into Objective C that compiles and runs pretty flawlesly on an iOS device, and it's fast. It's not emulated, it's actually a port of Android's core libs right into Objective C. Amazing work.

    I started working with Swift recently and it's pretty cool itself. Apple's answer to C# and Java, basically. I like that they released it free and open source for Linux. It's weird to program in until you get used to the weird memory management stuff but, hey, code runs so much faster without garbage collection.
  • ddriver - Sunday, January 24, 2016 - link

    Objective C is an atrocity. Moving away from it in favor of swift is one of the few moves apple can be commended for.

    Apple have taken advantage of native code, which has resulted in better user experience than android, even when their hardware was mediocre. Because native code is way better than java.
  • Relic74 - Saturday, February 27, 2016 - link

    Developing apps that take advantage of the iPad Pro's hardware is just the tip of the iceberg. iOS needs a complete overhaul as in it's current state it's lacking just to many features to be considered anything approaching a Pro OS.

    The iPad Pro is my first iOS device, I've played with them over them years but I never really liked iOS, it just always felt extremely restrictive to me. When the Pro came out with iOS 9.2 I was intrigued and started to read up on it, the reviews were solid and everyone I talked to who owned one, really liked them. So I made the plunge and bought one for myself. Now I already have a tablet, the new Pixel C in which I really like, even though the reviews on that haven't been so super. The biggest complaint was that Android isn't really a productivity OS. I found it to be quite the opposite, it's an extremely capable machine. So when I read that the iPad Pro is pretty decent on productivity tasks, I thought well if they thought the Pixel C wasn't up for the task and it is, than the iPad Pro must be something special.

    It's not, every reason why I avoided iOS all of these years is still present in the latest version, every single one. As I use CodeEnvy, a cloud based IDE to do most of my programming, I assumed the iPad Pro would be able to handle to handle my work flow. It's nothing outrageous what I'm doing or expect, simply using the CodeEnvy app, Prompt 2 (a terminal app) and Chrome. I also needed Excel to calculate trade PNL's. Within the first hour of using the iPad Pro it was more than apparent that it just wasn't meant for productivity work or at least nothing on the level that I required and didn't come lose to the Pixel C's abilities.

    First, I needed to run the terminal app in the background, compiling apps can take a while, plus I run scripts and monitoring applications. However after 3 minutes iOS would terminate it's connections. After some research it seems only about 1% of the apps in the App Store can actually run in the background for extended periods of time, mostly GPS and music apps. Than their was the problem with app resolutions, more than 80% of them I had installed didn't support the iPad Pro's resolution. So again after some research it seems only about 10% of the apps available actually support it's resolution, these unsupported apps also use another keyboard, one that is extremely basic and missing many of the features of the systems default. Now, app developers are working on this problem but the real problem, which is that apps in iOS are resolution independent in the first place just isn't a good idea. However it seems that their is no other way to do it because of this so called Walled Garden Paradigm.

    Apps in iOS are basically islands and in some weird way are even like OS's themselves, they basically have to fend for themselves With little contact to actual system except through hacks, okay, API's but it sure sounds like a hack to me. So every time a new feature is added to iOS app developers have to manually update their code to support it. Which brings me to the next issue, dual app view, only about 120 apps or so support it, again, we have to wait for the app developers. Now I'm not saying Android is the better option for any of you, it's all about preferences but when I enabled the dual app view feature in Android 6.0, every app from that moment on supported it. Further, every app I have installed into my Pixel C supported it's resolutions. When I connect a monitor to it, everything is supported, resolution, aspect ratio, I can even change the DPI to make it look more like a proper desktop UI and it supports extending the desktop, not just mirroring. Since the Pixel C has a USB C, I'm using the same port-replicator I bought for my MacBook 12" which has, HDMI, SD Card reader, 2 USB 3, mini USB and Ethernet, connecting a display to the Pixel C couldn't be easier. When I connected my monitor to the iPad Pro it looked like complete crap, black bars, the DPI was so large it looked like a child's toy and it just supported mirroring which absolutely sucks because you can't have two monitors.

    File system or should I say lack of because except for iCloud, iOS doesn't have one, it depends on it's apps to manage them. This is absolutely ridiculous and frankly Apple should be ashamed of themselves for leaving it this way for the last 8 years. Dealing with files in iOS is a complete nightmare. Every time I grab a file from the cloud I end up creating at least 4 copies of the same files because when you send a file to an app, it sends a copy, leaving the original in the app your sharing from. So keeping track of which file is the latest version is impossible. Why am I sharing in the first place, on every single mobile device I've ever used, the sharing feature was used to send content to an online source, never was it used as a method to manage files, especially not as the primary method. Also I have yet to have seen an app that can Share to every compatible app installed, their always missing apps in the share list, why because unlike Android which creates it's Share lists dynamically on a system level, the app developers for iOS apps have to manually create a Share profile, which means apps can pick and choose which apps they want to support. When you install the DropBox client, every app that can create a file from that time on should be able to Share to it, period. Instead we have to wait for the app developers for everything in iOS. People say that Android is fragmented, fine but so is iOS, except in it's case, it's the apps that are fragmented. Anytime a new feature is added, every app should automatically be able to do it because the system manages it, not the apps.

    The keyboard, I first bought the Apple keyboard, however I really didn't like the way it felt to type on, I missed having the function keys and the biggest issue, no backlite, something I simply cannot live with out as I type at night in bed a lot. It also doesn't provide any protection so I had to buy the hard case, 200 bucks + for a mediocre keyboard. So I bought the Logitech, a much, much better typing experience however there is one problem that became hugely apparent while using it. I wanted a mouse, not every time, just when the keyboard was connected. Why, well like Tim Cook said about notebooks with touchscreen's being a failed idea mostly do to poor ergonomics, the user has to constantly reach up to navigate the UI (get's old real quick), the iPad Pro, ironically, falls under the same category. Foot in mouth next time Tim, I'm sure you didn't realize at the moment that you were also talking about the iPad Pro but it's the same exact thing.

    The Pencil, I'm not an artist so I can't really say if it's good or not. The one thing I do know is that I can't use it throughout the system. Something I desperately wanted to do, so in the drawer it went, instead I use a Wacom, has pressure sensitivity, palm rejection and writes great, no lag. In fact I can't tell the difference between the two when using apps like EverNote, Bamboo Paper, OneNote, etc. the iPad Pro is a finger print magnet, I just wanted a stylus to navigate the UI with, also without a mouse the Wacom is the closest thing I can get, works a lot better with it than without when using the keyboard, that's for sure. Is there an actual Apple device available without compromises, there is absolute zero excuse for not allowing the Pencil to function throughout the system. This idea that the iPad Pro is a touch device only completely fell apart the second Apple made the Pencil and keyboard, two accessories that break this touch only paradigm. The only reason why Apple is doing this is to save a little face from all these years of saying the stylus is garbage. This is also why I'm pissed that Pro doesn't have mouse support. The OS certainly supports it by the way, my brother has an iPad Air 2 which is JailBroken and he installed mouse drivers just fine, works great.

    There is potential here, however even with great apps the blatant problems in iOS prohibit it from ever becoming a proper productivity tool. Now I fully realize that there are plenty of people that get by just fine with using the iPad Pro, I'm just not one of them. The Pixel C is a much more capable machine for what I do, I have every app that I need which by the way are the same exact apps I had installed on the iPad Pro so I don't get this, no apps for Android tablets thing, I have over 60 apps, all of them look and perform great. In fact, they actually look better on the Pixel C because they all support it's resolution. I have a stylus, the same Wacom. I use for the iPad Pro. I have an actual file-manager with all of my files in a single area, organized by folders. I can access my firms secure NAS drive using Open ID, I have all of my cloud storage, other computers, external HD's and FTP servers mounted as local assets, so when I click on save, the file is saved directly on whichever remote storage I choose. None of that, click on Share BS. When I'm editing a file and need to use more than one app, each app uses the same exact file, no creation of multiple files from Sharing, just open, edit, save, go to other app, open, edit, save. I can find any file in less than a minute, I can find every file that contains a persons name inside of the files In less than a minute. I tried to do this in iOS, I just gave up, finding files in iOS is like trying to find Noah's Ark in Turkey. Zipping and sending files in iOS, well, just also sucks, hopefully the files your sending aren't located in more than 2 apps. I use the Pixel C as a desktop computer as it has mouse support and looks great when connect to a monitor with extending desktop capabilities. Since I can run Linux desktop applications and quickly mind you, it actually makes for a decent desktop machine, however I just purchased an Nvidia Shield TV, installed Arch Linux on it and am now using that as my desktop computer. The performance of the Pixel C was so good when running Linux apps that the Shield TV was a no brainier. Yes, there are GPU drivers for it, in fact my CUDA applications work great on it. I can encode a video file using the GPU to compute faster than most laptops using their CPU's.

    Write now I am compiling an app in the background, while downloading a 20GB .rar file to a connected HD, while streaming a movie directly from OneDrive without having to download it first, to my sons TV in his room, I have Gimp running on my monitor as I was editing a picture, (I'm running Arch Linux in a Chroot under Android, to use applications I just start them up through an X-Terminal, works great), while I'm typing this up in Chrome on the Pixel C itself. The iPad Pro doesn't come close to that level of multitasking, running two apps in a split screen view is a nice feature however I would give it up in heart beat to be able to run any and all apps in the background.

    I'll end it here, the iPad Pro is still just an iPad, it's not a laptop replacement, it's not a productivity machine, it's an iPad. A content consumption device, just with a larger display. Those wanting one, wait, at least until version 2 comes out. There are just tom any issues that need to be worked out and most importantly, no apps that really take advantage of it.
  • boozed - Friday, January 22, 2016 - link

    MaxiPad, surely.
  • definitelyReal - Friday, January 22, 2016 - link

    Lol
  • xerandin - Saturday, January 23, 2016 - link

    You win this comments section. Not really worth much, but it's better than the guys in here defending a product that has left most of everyone everywhere completely nonplussed.
  • Constructor - Saturday, January 23, 2016 - link

    Ideologue, much?

    I've simply bought it because I wanted to use it, and I do. Every single day. And it is fantastic.

    If you're "nonplussed" by it, you're likely asking the wrong questions to begin with.

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