Odds are, you bought that laptop, smartphone, or tablet because it’s something you can easily take with you. So when it comes to battery life, the longer, the better. But not all batteries are created equal.

In fact, battery life within each category of mobile devices varies widely. In our labs, we've recorded battery life of just 3.5 hours on a couple of laptops, and as few as 5 hours on some tablets. Several smartphones we tested provided as little as 8 hours of talk time.

Those numbers got us wondering—which mobile products offer phenomenal battery life? Here’s a list of the tablets, smartphones, and laptops with batteries that don't tire easily.

—Donna Tapellini

Toshiba Portege Z30-BSMBN22 ($900, Intel Core i3, 4GB memory, 128GB solid-state drive)

Toshiba’s new Portege kept working for 19 hours in our battery-life tests, making it the longest-lasting laptop in our Ratings. It’s a 13-inch model that’s also quite light at 2.6 pounds, and an excellent performer.

Apple MacBook Air 13-inch MD760LL/B ($899, Intel Core i5, 4GB memory, 128GB solid-state drive)

Lasting 16.25 hours, battery life on this MacBook Air will let you get two solid days’ work in. It’s thin, it’s light, and it’s an excellent performer. (This is the prior-generation MacBook Air. We haven’t tested the newest one yet, but we expect battery life to be at least comparable.)

Lenovo ThinkPadX1 Carbon ($1,200, Intel Core i5, 4GB memory, 128GB solid-state drive)

Battery life on this 14-inch laptop was 13 hours, the longest of all those we tested in this size category. It’s also the lightest of its size, weighing in at 2.9 pounds. Performance was excellent, and the display is one of few with a matte screen, making it less reflective than others.

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Sony Xperia Z3 Compact Tablet ($500, Wi-Fi, 32GB)

How does 16 hours of battery life sound? This innovative tablet is also waterproof. (Yes, we dunked it!) The Z3 is also notably thin and light. Performance was excellent, so it’s great for playing games.

LG G Pad 7.0 ($150, Wi-Fi, 8GB)

At 15.9 hours, battery life on LG’s G Pad almost matches that of the Sony model. But the G Pad puts much less strain on your wallet. It’s also quite light.

Amazon Fire HDX 8.9 ($380, Wi-Fi, 16GB)

Another tablet with more than 15 hours of battery life, the Fire HDX has the largest screen of the tablets noted here. Performance was excellent. If you want to take full advantage of the Fire HDX, consider signing up for Amazon Prime, a $99 annual subscription that gives you access to free movies and TV shows, as well as other content.

Samsung Galaxy Note 4 ($825 retail)

The Note 4 will let you chat for 24 hours without needing a charge. Even better, it charges back up quickly. It’s got a dazzling 5.7-inch display, an impressive camera, and an innovative stylus.

LG G3 ($580 retail)

Another model with 24 hours’ talk time, the LG G3 sports a phenomenal display. The slim, curved design makes it comfortable to hold despite that large 5.5-inch screen. It’s also got one of the best laid-out virtual keyboards we’ve seen, so if you do a lot of typing on your phone, this is one to consider.

Apple iPhone 6 Plus ($850 retail)

Battery life with this model is significantly better than that of prior iPhones. With the iPhone 6 Plus, you’ll get 17 hours of talk time, our tests showed. That’s in addition to a great display and sleek design.

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