The Samsung Galaxy S4

The Galaxy S4 handset steadily draws from the same design language as the S3, but takes almost every spec to an extreme -- the screen is larger (5 inches), the resolution greater (1080p), the battery capacity higher (2,600mAh), the processor faster (1.9GHz quad-core or 1.6GHz octa-core), and the rear-facing camera stuffed with more megapixels (13, to be exact). But, once you've gone through the features checklist (which also includes lots of internal and external storage space and RAM), it's the software extras that Samsung continues to lean on to keep its phones one step ahead of the competition.
Standing at 136.6mm tall by 68.9mm wide (5.4 inches by 2.7 inches), the Galaxy S4 fits right in between the GS3 and the Galaxy Note phones. It's large, to be sure -- very large -- but since I've grown used to holding big handsets, it didn't feel overwhelming in my hands. A more dimpled finish on the white version I held reminded me of the Galaxy S2, in contrast to the GS3's silky brushed feel.
On the back, there's the 13-megapixel camera, a jump up from the GS3's 8-megapixel lens. Even though the number of megapixels isn't everything, Samsung has had a good track record with images so far. The shooter has an LED flash and records 1080p HD video.

OS and apps
The Galaxy S4 runs none other than Android 4.2.2 Jelly Bean, the most up-to-date version of Android you can get right now. Riding on top of it as usual is Samsung's Touch Wiz overlay, a customized interface that I, for one, think is getting a little long in the tooth. Also, keep in mind that the next Android OS, Key Lime Pie, should appear when Google I/O opens on May 15.

Eye-tracking gestures
Conflicting rumors painted a scenario where you'd scroll the screen with your eyes using eye-tracking software within the GS4.

Air View and gestures
While you can make googly eyes at the GS4, most gestures are still reserved for your fingertips. Hovering features known as Air View make their way from the stylus-centric Galaxy Note 2 andGalaxy Note 10.1 tablet to the Galaxy S4, but replace the stylus with your digit.

Cameras and video
If the promise of the GS4's 13-megapixel images doesn't wow you, Samsung is hoping that its refreshed interface and enhanced features will. Perhaps the most out-there is the dual-shot mode, which takes photos and video from both the front- and rear-facing cameras, and combines them into one.

Performance
While the Galaxy S4 will look the same everywhere in the world, it won't necessarily have the same motor under the hood. Your future GS4 handset will either thrum from a 1.9GHz quad-core Qualcomm Snapdragon 600 series processor, or from a 1.6GHz eight-core chipset,Samsung's Exynos 5 Octa silicon.
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