Intel has wanted to be a part of the smartphone market since 2005. Its Atom line of processors and systems-on-chip was developed for this market, and each iteration has been smaller and more tightly integrated. With Medfield, announced earlier this year, the company finally has the chip it needs to take on ARM head-to-head. Intel has partnered with Indian manufacturer Lava International to bring its chipset to market, and the result is a new Android phone: the Xolo X900.

The phone is not available in the US. It sells in India for about $420. The phone's specification is at the upper end of mid-range: 1024×600 4" screen, 8 MP rear camera with 1080p30 recording, 1.3 MP front camera, and 16 GB of storage. It runs Android 2.3.7, with an upgrade to version 4 due later this year. So far, so ordinary. The thing that sets it apart from its competition is its processor. It's called an Atom Z2460: a 1.6 GHz single core, hyperthreaded 64-bit x86 CPU, paired with a 400 MHz PowerVR SGX 540 GPU, and 1 GB RAM.

AnandTech and ExtremeTech both have good, thorough reviews of the handset. The consensus is, well, it's a typical mid-range Android phone, running essentially stock firmware (though it also includes the Swype keyboard). The camera controls are probably the only unusual part—the X900 has a lot of settings and allows quite fine control of the camera's behavior.

The phone's single-threaded performance, particularly when running JavaScript, is strong. Its graphical performance is decent, its all-round performance is solid. Battery life is mid-range. All in all, it's unexceptional: not the best Android smartphone, but not the worst either.

In practice, aside from the Intel Inside logo on the back, and occasional software incompatibilities (Intel has software on the phone to translate native ARM binaries into x86, and while it works almost all of the time, a few applications break), you'd never know it wasn't just a regular ARM handset. It's just an Android phone.

But for Intel, this is a landmark event. The company has got a smartphone, and it's a credible mid-range, mid-market handset, that works, and doesn't suffer any crippling disadvantages due to its x86 processor. That alone is a triumph.

Even a year ago, this was unthinkable: Intel's previous attempt at a smartphone processor, Moorestown, was ignored by OEMs because it was too big and too complex, requiring too many different chips. Medfield increases the integration, going from from Moorestown's five chips (processor, chipset, power management, RAM, wireless) to a much more palatable two or three (SoC, RAM, which can now be package-on-package and hence "integrated" with the SoC, and wireless); it also cuts power consumption further still.

Medfield isn't going to trounce the ARM competition. The high-end A9 and Krait processors are still faster. They still offer better power efficiency. Some of the ARM SoCs integrate better GPUs, too. But Medfield is just the first true Intel smartphone chip: future offerings will be faster and lower power. Medfield is still built using Intel's 32 nm process. Next year, Intel will release Silvermont, using the company's cutting-edge low-power 22 nm process. The year after will see Airmont on 14 nm.

These changes will slash power consumption and, critically, can't easily be matched by the ARM vendors: Intel has a considerable process advantage over other chip fabricators, and will beat them to both 22 nm and 14 nm, probably by several years. These improvements threaten to turn Atom from a credible alternative to ARM—which Medfield is—to a class-leader.

Later this year, Intel will be shipping Medfield's bigger brother: the Atom Z2480, sporting dual cores and an improved GPU, the SGX544MP2. This part is aimed at the tablet market—particularly Windows 8—and should be competitive with ARM parts there, too. Unlike the ARM-only Windows RT, Windows 8 on Atom will be able to run regular desktop software, too, which could make it even more compelling.

For the longest time, Intel's smartphone and tablet ambitions were but a pipe dream. They're now a reality. Though eminently competent, the mid-range Medfield isn't going to upset the smartphone market too much. But as a harbinger of things to come, it should have ARM vendors scared.