I own the Karbonn A1 and its a good phone for Rs.4350/- on some of the online websites. The battery dies in about 2 days with average talktime and Internet usage. One needs to kill background applications to make the battery last longer. the screen display is very good and the graphics quality is awesome. The sound though is not too pleasing Rajeev_Vermacially at higher volumes and tends to crackle. the camera is good with 3.2 MP without flash and outdoor photography is marvellous while indoors the camera tends to lag a lot. The market place has several software to download and mostly free. The 3 G capability is good though I have not yet tried it on the long run as Loop Mobile does not provice 3G facilities yet. The EDGE technology over GPRS is good for high speed internet connectivity and the phone can be used to become a HOTSPOT when one does not have a Wi-Fi connectivity for their laptops or TABS.
The built-in Wi-Fi is great however the phone switches to Power Saving mode several times therefore the Wi-Fi connection needs to be reconnected often.
Its a single SIM GSM phone and operates on an Android 2.2.2 Froyo OS, with 4GB NAND and 2 GB DDR Ram. the processor is little underpowered @ 600 MHz(ARM processor) comparing to its counterparts at 700MHz.+
Touchscreen is good however resistive over capacitive is a bit of a pain until you get used to it. The G-Sensor function works well and gives a better keyboard QWERTY feel when held horizontal. the swipe feature of the keyboard is an added advantage and predictive typing makes it easier to type longer sentences and words and correct mistakes much easier than other touch phones.
Overall a good phone for Android lovers and a great entry level Android phone. Its very pocket friendly and the retails for around Rs.4000+ websites like Saholic, Ebay, Letsbuy etc.