Motorola C139 is a cellular phone designed and manufactured for Motorola by an ODM manufacturer. It addresses people with basic needs, and has limited features. This phone is currently offered on AT&T's GoPhone service, TracFone, Cellular One, and Net10. It is primarily focused for prepaid plans, and was claimed by a PC Magazine review to be the cheapest unlocked GSM handset.
http://www.pcmag.com/article2/0,2817,2104043,00.asp Motorola C139 - Reviews by PC Magazine]...
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