If you're going on a long journey, your tablet is likely to be your only source of entertainment. In these times of media consumption and gaming need, your tablet becomes your most important device so decent battery life is a must-have. This year, we've refined our tablet battery testing methodology and can now present it in a handy, easily readable graph. We've only included Android tablets and iPads here as they make up the bulk of the market. Android is represented in blue while iPads are in red.

How we test

To measure a tablet's battery life, we run a continuous video playback test. We made the video file using a handful of scenes from Spider-man 2, encoded to H.264 and looped dozens of times for a 20+ hour file.. We then play back the file and leave it running with the tablet's audio routed into a PC running recording software. When the test is done, we review the recording and see at what point the device switched off. In Android, we've always used MX Player for playback but when testing iPads we use the default video player. We also set the tablet to aeroplane mode, turn off any automatic brightness and sleep settings and set the screen brightness to 170cd/m2.

While putting the tablet into aeroplane mode turns off all of the wireless features and, naturally, extends battery life, it does mean that our tests are repeatable. The big problem with wireless is that signal strength can come and go, which forces the phone to adjust the amount of power that it uses constantly, causing variable results. For next year, we're working on a test that will use Wi-Fi and a streaming video, to give a closer and more accurate representation of real-world use. However, it's important to us that the test is consistent, so we can compare tablets with a degree of accuracy. Ultimately, how you use your tablet will define your personal battery life.

At Expert Reviews, our goal is to show which device lasts the longest in repeatable conditions , with the inference that longer-lasting tablets will outperform those with poorer results in real-world conditions.

Results

The difference between the best and worst tablet battery life from 2015 is a huge 8h 10m. Our best-performing tablet is the Lenovo Yoga Tab 3 , which managed 14h 49m, beating the brand-new Google Pixel C by 16 minutes and pipping the Dell Venue 8 7840 at the last, after it had held the top spot for most of 2015.

At the bottom of the list we find Asus ZenPad S8.0 , which managed only 6h 39m in our test. The budget Acer Iconia One 7 managed just a minute longer, putting it second-last. As much as we loved it for its rock-bottom price, the now-discontinued Tesco Hudl2 was third-from-bottom with a score of just 6h 58m. Amazon's ridiculously cheap Fire 7 tablet was impressive for the money, managing 8h 43m, although this still puts it well down in fifth-from-last. The larger Amazon Fire HD 10 , which we did not like at all, was a little better, managing 9h 8m.

Other noteworthy performances - although not particularly positive ones - come from the current crop of iPads, which respectively sit 12th, 14th and 15th out of 23 in our rankings. Bigger doesn't mean better when it comes to iPads, it seems, with the 12.9in iPad Pro down in 14th with a battery life of 9h 8m. The iPad Mini 4 performed best, with its 7.9in screen seemingly sipping power at a slower rate compared to the iPad Air 2 (9h 32m), managing a reasonable 10h 43m. It should be noted that iPads have ridiculously long battery lives in standby, though Android 6.0 has closed that gap considerably thanks its new Doze feature, but this is not something we currently test.

You can't buy Nokia's N1 here in the UK (but it's well worth importing) scoring a respectable 10h 47m. Nvidia's Shield K1 , which replaced the original Shield , achieved 12h 39m while its predecessor was still impresssive with 12h 9m.