Samsung SPH-M370

The good: The Samsung SPH-M370 has a familiar design, large, comfortable buttons, and strong call quality.
The bad: It's pretty bare-bones; a microSD card slot or music player on the M370 would be nice. You can't change the phone's text style or size, and the address book is relatively small.
The bottom line: The comfortable Samsung SPH-M370 is a basic flip phone that does what it says, unadorned and unembellished, and at the right price.

The quintessential flip phone needs two things: excellent call quality and large, easy-to-press buttons. Happily, Samsung's SPH-M370 for Sprint can check off both boxes. What you see is what you get with the simple, straightforward features and design; and at $19.99 with a new two-year contract, the price is just right.
Design
The M370's clamshell design is immediately familiar, but Samsung does add interesting touches here and there. In this case, it's the rounded-edge design, the nubbly gray finish on the face and back, and a slight curve at the upper portion of the phone that looks like someone pinched the top and pulled it forward.
It has a comfortable grip and dimensions that keep it small and compact, perfect for slipping into a front pocket or a cell phone pocket in a small purse: 3.8 inches tall by 2 inches wide by 0.7 inch thick. At 3.7 ounces, the M370 feels substantial, and the overall design is solid enough to take a beating.

The Samsung SPH-M370 (or just plain 'M370') is your classic, reliable flip phone.

The handset itself shows off its camera lens and 1-inch display on its face. The volume rocker is on the left (push it in to light up the external screen) and the Micro-USB charging port, the camera shutter button, and the 3.5mm headset jack are on the right.
The face flips open in a smooth arc over a large, thick hinge. Inside, a 2.4-inch QVGA screen (320x240-pixel resolution) looks colorful and bright. So long as you know to push the physical Menu button to get to most of the phone's options, it's easy to navigate around. The phone is fairly customizable, with options to pick wallpaper and clocks for both screens, set contrast, and control the brightness and backlights. You also have a say over text entry formats and ringers, and can turn location off and on; however, you won't be able to change the phone's font style or text size. By default, you'll hear typing tones loud and clear. They grated on my ears, so I immediately turned them to silent mode.
Below the screen, the navigation array and dial pad feature large, tactile, rubbery keys that are comfortable and responsive to the touch. They're backlit and separated, and there are a few bumpers for orienting your fingers on the keyboard if you're attempting to type by feel. The navigation array has the usual two soft keys, and the Talk, Back, and End/Power buttons surrounding the central navigation toggle. The toggle itself is quad-directional and has a Menu/OK button in its center. Few keys share tasks; one exception is the "1" key, which also launches voice mail by default.
Features
What you see is mostly what you get with the M730. There's room for 600 contacts in the phone's address book, plus each contact can have various phone numbers, e-mail addresses, IM handle, a birthday, a URL, notes, and a mailing address. You can also add photo ID, form a caller group, and personalize the ringtone. There are 10 preloaded ringtones you can choose from, or you can easily download some from Sprint's online store.

The large, tactile buttons make dialing a snap for fingers of all sizes.

In terms of tools, the M370 is well-stocked with the essentials: an alarm, a calendar, a calculator, a world clock, a memo pad, and a voice memo. It also has Bluetooth support and multimedia text messaging. There's a simple browser that isn't very fast or polished, but it does the job when you need to look something up. Just remember that you'll have to pay for data, which tends to add up.
There is some room for extras, if you download them, again from Sprint's various stores. That includes games, ringtones (they call them "ringers"), screensavers, and other applications for things like weather and instant messaging.

It's best not to rely on the M370's 1.3-megapixel camera, but it works.

As far as cameras go, the 1.3-megapixel shooter on the M370 really isn't much, but I'm glad to see it here nevertheless, and it's just fine for converting shots into photo IDs.
Performance
Since making and receiving calls is this phone's chief purpose, I spent a long time testing the dual-band Samsung SPH-M370 (CDMA 800/1,900MHz) in San Francisco, using Sprint's network. Call quality was very good overall: loud, clear, and mostly smooth. I was able to place calls all over the country to landlines and mobile phones with mostly consistent results. A couple of calls to the same number yielded a steady stream of warps and odd digital noises over a 15-minute period, but other calls were much more level.
Callers generally liked the sound they heard at their end. Overall, they said my voice was loud and clear, and they didn't hear any distortion. However, various people helping me analyze the sound found "the quality isn't perfect," I didn't sound quite as "full" or "rich" as I do in the flesh, and the audio quality degraded a bit when my voice hit high frequencies. And my 91-year-old grandma suggested that I sounded ever-so-slightly metallic.
Samsung SPH-370 call quality sampleListen now:

Speakerphone also performed well on the whole when I held the phone at waist level. I had to raise the volume a tick to hear as well as I wanted. Voices sounded a little muffled on both ends, but the quality was on point, if perhaps a little tinny. Callers liked the volume and the quality in general, but also noted that the sound had the hollow and projected quality of all speakerphones.
The M370 doesn't demand much, so the 192MHz Qualcomm QSC6055 processor is just fine. It has a rated battery life of up to 5.4 hours on its 1,000mAh battery, which isn't bad, and up to 10 days standby.
The FCC's test of radio frequency emissions puts the M370's digital SAR at 0.75 watt per kilogram.
Conclusion
I know plenty of people seeking a sturdy, reliable, and dead-simple phone--among them my non-techie, budget-conscious mother; friends looking for an extra line; elderly neighbors who really don't want the fuss of learning to use a smartphone; busy moms whose brood of spirited young tends to break handheld electronics; and a few readers who want one to complement a smartphone that's mostly used for data and can't simultaneously do voice. To all of them I present the M370. It's simple, it works, it looks fine, and it costs just 20 bucks. Enough said--don't you agree?