The Samsung Galaxy Note 4 packs in a sizable 3220mAh battery which, unlike many of its rivals including the Nexus 6, iPhone 6 Plus and even the new Galaxy S6, is removable.

For those who always find themselves away from a plug socket the ability to swap out a dead battery for a fully charged one is an enticing proposition.

In fact it houses the same size battery as the newly announced Nexus 6, while the QHD toting, 5.5-inch LG G3 can only boast a 3000mAh power pack.

It's a touch bigger than the 3200mAh battery inside the Galaxy Note 3, and with the Note 4 having a vastly enhanced display you may initially worry about its battery life potential.

The good news is I had no trouble getting the Samsung Galaxy Note 4 to last a whole day on a single, with it generally having 20%-30% of juice left in the tank when I got into bed.

Samsung Galaxy Note 4 review

That's with moderate to heavy usage, with a couple of hours of Spotify music, a couple of hours of gaming, some light web browsing, emails plus a variety of calls, texts and social media activity.

Unlike the Samsung Galaxy S5 or HTC One M8 though, the Note 4 won't go for almost two days - you'll still need to practice the nightly charging ritual here, but you're unlikely to ever find yourself dashing to a power point.

Running the TechRadar 90 minute HD video test with the brightness on full and various accounts syncing over Wi-Fi saw the Galaxy Note 4 drop 19% - a respectable performance that puts it above the iPhone 6 Plus (27%) LG G3 (25%) and HTC One M8 (23%).

The battery performance on the Note 4 isn't quite as good as the Galaxy Note 3 then (which lost 13% in the same test), but with day-to-day usage you're unlikely to notice much of a difference.

Put that QHD screen to work for an extended period of time though and the percentage will tumble, but perhaps not as fast as you may expect.

Samsung Galaxy Note 4 review

If you do find yourself in the red zone and near a plug Samsung's fast charge cable is able to recharge approximately 50% of the battery in just 30 minutes, providing a welcome boost of power.

The cable (and plug) is included in the box, so you won't have to go out and spend extra cash on another lead.

There will be times though when you're not near a power source, or don't have the correct cable to hand, but the Galaxy Note 4 has you covered here as well.

Samsung's impressive power saving mode which has featured in the likes of the Galaxy S5 and Galaxy Alpha also finds its way onto the Note 4, allowing you to make the most of those last few drops of juice.

Samsung Galaxy Note 4 review

You get the choice of 'power saving mode' and 'ultra power saving mode' on the Galaxy Note 4, with the former restricting background data and performance while also giving you the option to switch to a greyscale interface, saving you precious power from the QHD display.

Ultra power saving mode is far more aggressive, as it totally changes the interface to one which gives you access to just a few core apps (phone, texts, emails, web browser) as well as providing a simplified greyscale design.

When turning on this mode the Galaxy Note 4 makes some pretty bold claims, including "days" of standby life, but to be fair to Samsung it does make a difference.

It's not a mode you'll find yourself using all that often, but when you do hit the red zone - and at some point you probably will - you'll be thankful it's there.