Samsung has updated its flagship phones with under-the-hood changes and a bigger screen, while LG has made more radical changes to its most popular phone series.  

The Korean electronics giant rolled out the Galaxy S7 and S7 edge on Sunday at Mobile World Conference in Barcelona.  Both models mark the next generation of Samsung’s most popular smartphones and the next stage in its fierce rivalry with Apple.

Galaxy S7 edge: Samsung surprised with the new version of the curved-screen model by bumping up the display size to 5.5 inches from 5.1 inches. (The previous-generation Galaxy S6 and S6 edge phones had both been 5.1 inches.) The display retains the same “quad HD” resolution as the previous generation and the same curved design that “waterfalls” on both sides. Samsung also tweaked the back of the phone, giving it a very slight curve to make it easier to hold.

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It’s worth noting that with the bigger 5.5-inch display, the S7 edge is now on equal footing with the 5.5-inch iPhone 6s Plus, Apple’s largest smartphone.

The biggest under-the-hood change for the S7 edge is the battery, which has been increased to 3,600 mAh from 2,600. That’s a big boost and should help Samsung address the battery-life shortcomings of the S6 edge.

Galaxy S7: The 5.1-inch flat-screen S7 saw the fewest cosmetic changes. Like the S7 edge, it gets a curvier back for better ergonomics.  And like the S7 edge, it also gets a bigger battery, now 3,000 mAh, up from 2,550 mAh in the S6. A bigger battery invariably makes a device heavier but that’s a tradeoff Samsung is willing to make to improve battery life.

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Common specs to the Galaxy S7 edge and Galaxy S7: The biggest spec change common to both phones is the camera. Though seemingly counterintuitive, Samsung actually dropped the megapixel count to 12MP in the Galaxy S7 from 16MP in the S6. But less can be more in the case of camera sensors. The pixels are now bigger and Samsung claims the larger pixels let in more light, resulting in better low-light photos.  And Samsung has improved the lens too to allow more light through.

Both devices are water and dust resistant and both get Android 6.0 Marshmallow, the latest Android operating system.

The phones will be available from U.S. carriers on March 11.  Pricing should be similar to the previous-generation S6 edge and S6, Samsung said.

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LG G5: Though invariably overshadowed by Samsung, the smaller South Korean phone maker made more radical changes with the new G5 phone.

The killer feature of the slightly smaller phone (compared to the G4) is modularity. By pressing a button, the bottom of the phone slides out, which allows you to not only swap out the battery for a fresh one but add upgrade modules too. For example, there's a module for upgrading the audio and another one that adds features to the camera like better zoom and a bigger battery.

And speaking of the camera. The LG G5 has both 8- and 16-megapixel sensors on the back, located on either side of the LED flash. The secondary 8MP sensor allows wide-angle shots, according to LG.

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The all-metal G5 also has some of the more expected tweaks like a faster processor and ships with Android Marshmallow.  

It will ship in April. Pricing will be announced before then.