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Karbonn KT21 Express vs Karbonn A 1 Size compare


Karbonn KT21 Express Remove phone

Posted: 25 Apr 2012
Market Status: Released

Karbonn A 1 Remove phone

Posted: 02 Jul 2011
Market Status: Released

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Device typeFeature phoneSmart phone 
OS Android (2.2) 
Dimensions 4.20 x 2.33 x 0.55 inches (106.8 x 59.2 x 14 mm) 
Weight 3.70 oz (105 g)
the average is 5.1 oz (146 g)
Physical size2.8 inches2.8 inches 
Resolution 240 x 320 pixels 
Pixel density

Pixel density - The pixel density of a display represents the number of pixels over an area of one inch. It’s measured in “pixels per inch”, or ppi. The higher the number, the more detailed and good-looking the display is.

 143 ppi 

Technology - There are two main screen technologies currently used in phones and tablets: LCD and AMOLED. The former usually features a light source and liquid crystals, while the latter is based on organic light-emitting diodes. Newer LCD variations like IPS-LCD and Super-LCD allow for very accurate color reproduction and very wide viewing angles, where no significant image quality loss is observed. Current AMOLED screens differ in such a way that they can exhibit much more saturated colors (sometimes too much) and incredibly high contrast levels, which is due to black color being completely black in AMOLED displays.

Screen-to-body ratio 38.45 % 
Colors 262 144 
FeaturesProximity sensor  
Camera3.2 megapixels3.2 megapixels 
FeaturesDigital zoom  
Built-in storage 4 GB 
Storage expansionmicroSD, microSDHC up to 32 GBmicroSD, microSDHC 
Talk time 4.16 hours
the average is 13 h (796 min)
Stand-by time 10.4 days (250 hours)
the average is 17 days (419 h)
Capacity1000 mAh1100 mAh 
specifications continue after the ad
Music player   
Filter by Album, Artist, Playlists 
Features Album art cover, Background playback 
RadioFM, Recording option  
YouTube player Yes 
Internet browsing
Built-in online services supportFacebook, YouTube (upload)  
GSM900, 1800 MHz850, 1900 MHz 
UMTS 850, 1900 MHz 

Positioning - This field shows the positioning systems supported by the device. There are three main types: GPS, A-GPS and GLONASS. GPS - This is one of the most widespread global positioning technologies, developed and maintained by the U.S. government. It uses satellites in order to detect your location. Works best in clear weather. A-GPS - A-GPS stands for Assisted GPS and is the industry standard for positioning and navigation. “Assisted” means that it can use local wireless networks, in addition to satellites, for quicker and more precise localization. GLONASS - GLONASS is a global positioning system, developed by the Russian Federation. It’s very similar to GPS, but isn’t so popular in cell phones.

Wi-Fi Yes 
Mobile hotspot Yes 
USB USB 2.0 
Features Mass storage device, USB charging 
Other Tethering 
Other features
Notifications Music ringtones (MP3, WAV, AMR, MIDI), Polyphonic ringtones (64 voices), Vibration, Speakerphone 

To see the full specifications with in-depth details click here.

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