OK. So a few weeks ago I bought the Motorola c139 phone off of Tracfone.com. Here's how it worked out:
Size and Appearance
The phone is pretty small. It's not a Razr or a c261 but it's not huge either. It has rubber inserts on both sides of the phone for something that's a little easier to grip than the semi-glossy silver plastic. The buttons are rubbery and sort of difficult to press at first but eventually they'll become easier. Overall, the phone looks nice, but pretty basic. Oh, and the Tracfone logo is happily only on the back of the phone, with Motorola's logo sowing up prominently on the phone.
This phone seems to get pretty good reception actually, but voice quality seems wierd sometimes for some reason or other. But usually it's nice. It may not measure up to, say, a Nokia 6010, but then again I don't have a cingular contract SIM that is handy so I can test the two side by side (I set up both teh 1100 and the c139 to run on Cingular for the widest coverage range and since I already have a T-Mobile To Go phone).
Due probably to the phone's tiny, though color, screen, highly convervative backlight settings (you can't read the display after the backlight goes off...at all...though it is still on), plus its monophonic ringtone speaker, plus its using GSM, this phone really sips battery life sparingly from its relatively large battery. The result: a week between charges with moderate use...mostly the included, entertaining but over-simple "Spring Ball" game but some talking as well. That's pretty darn good...as in maybe twice as good as my camera phone. But the camera phone has an external color display about as large as this phone's only display, the camera phone has poly ringtones, and the camera phone's battery is smaller. But the fact of long battery life remains...
Screen and User Interface
The c139's screen, as said above, is about the size of a midrange phone's external display. OK...maybe a little bigger. But not much bigger. It's only 96x65 pixels anyway, and it doesn't make as good use of those pixels as, say, a Nokia phone. The graphics in general are somewhat cartoony and there must not be more than about 32 of them that Motorola actually uses, even though the display is full 16-bit (65,536 colors). That's pretty sad. But it still has to be noted that the display is TFT, which is nice considering the phone is a mere $20 at Tracfone's website (they're out of the phone right now).
As to the interface, Motorola doesn't make the most intuitive UIs (Nokia does, with LG and Samsung coming up next I think), and the c139, with its center button being the MENU button instead of the SELECT button things are somewhat confusing. It has a 4-way D-pad but the only place you can really put it to good use is when playing the onboard games, and even then it's not that great. I would trade the left, right and center buttons for a better UI, personally. Then again, if you like Motorolas this may be OK for you.
Ringers and Vibe
Tracfone.com errs very much when it says that this phone has polyphonic ringtones; it doesn't. And the monophonic ringtones sound pretty gross for the most part, even out of beat at times. Not good. Also, PhoneScoop says that the phone includes a ringtone composer. It doesn't. The tones get reasonably loud at the highest setting, and interestingly can hardly be heard even with your ear to the phone at the lowest setting.
As far as vibrate alert goes this phone is similar to the Samsung a820 in that the vibe is not too strong but merely OK. It doesn't vibe to the music though.
All in all this is an OK phone if you want some sort of color screen (why I don't really know, at least on such a low-end model) and great battery life. One beef though is that all new GSM Tracfones now charge 0.3 units for incoming text. REVOLT! Anyway, at $20 this is an OK phone for the money, especially if you want as much GSM coverage as you can possibly get in one phone for US use (when activated on Cingular). But if you want features, I would wait for the new crop of phones, most notably the Nokia 1112 at this price point (the c139 may go back up to $30) or maybe even get the Nokia 2126 if your area has a good CDMA provider that Tracfone is with, though if you use the 2126 you'll have to live with roaming fees, slightly more expensive (0.5 vs. 0.3 units) text and a bit worse battery life.
But the c139 is still an OK phone if you just want something to make and receive calls, plus send and receive the occaisional text, with.