The ZTE ZF721 is a cellular based home phone service.
- Chipset Qualcomm QSC6270 single core
- 128MB maximum internal storage
- 3G – UMTS: 850/1900MHz
- GSM/GPRS/EDGE: 850/1900MHz
- Approximately 3 hours talk time and 25 hours standby time in the event of a power outage.
The ZTE ZF721 does not work with fax machines and security systems. It is not clear why as the modern 3G mobile network has adequate bandwidth. The cellular network was designed for voice only and not for other services which was at the time handled by land lines. The long term changes in cost did not be considered early on. Instead the frenzy of tower installation took advantage of comparatively high rates early on.
Recently cellular rates have come down substantially and they can be less costly compared to a landline.