The Karbonn K21 Star is a basic dual SIM phone with a TFT display of 2.4-inch. It has a resolution of 240 x 320 pixels. The device has a rear camera of 1.3MP with digital zooming. It is available only in black colour.
The Karbonn K21 Star has a very low internal memory and can be expanded up to 16GB with the help of an external microSD card. The device is powered by a 1000 mAh li-ion battery which gives long talk time hours. On the connectivity end it has GPRS for internet access. It also has Bluetooth for connecting it to other devices and transfer of files. The Karbonn K21 Star features an FM radio which has a recording option for entertainment means.
The Karbonn K21 Star is a low budget phone. For people seeking phones with long hours of calling, it is an apt device. The phone is lightweight for ease of handling. It also comes with an FM radio for entertainment needs. But the lack of an USB port might be a little problematic.