This probably is the shortest review on my blog. Simple reason being the phone’s similarity to it’s sibling – the Karbonn A9+, which has been reviewed extensively on this blog.

Display

The principal difference between the A21 and the A9+ is the larger screen on the A21. While the A9+ display measures 52 mm x 87 mm (4524 sq. mm area), the A21 display measures 56 mm x 99 mm (5544 sq. mm area). Thus the A21 features a hopping 22% bigger display area. Resolution wise, the A9+ features a resolution of 800 x 480 pixels (384000 pixels area) and the A21 features a resolution of 960 x 540 pixels (518400 pixels area) which turns out to be a even bigger 35% more number of pixels.

Issues

Compared to the display of the A9+, the A21 display is not as good. The screen test of the A9+ reveals gray shades that are uniform and neutral. The same test run on the A21 results in gray shades that are distinctly colored in hues of red, green and blue. The contrast range in A9+ is also superior with clear bands visible from Contrast of 0% – 100%. The A21 display does not show the darkest two bands with enough separation.

Battery

The A21 also features a Li-Ion battery with slightly higher capacity (1800 mAh, versus 1420 mAh battery on the Karbonn A9+).  The additional capacity should help because the phone has a larger display to power. In reality, the battery does even more. I have been installing apps on the phone for over an hour (over WiFi) and the drop in battery is very reasonable when compared to the A9+ (which becomes alarmingly low in the same period with the same activity).

Note that if the battery gets deeply discharged, the phone may not power-up even with the charger connected. In fact, it may not even appear to be charging. Just leave it connected to the charger. In a few minutes, the battery will charge sufficiently and the battery charging animation will show. At this point, you can power on the phone.

Issues

It is interesting to note that the battery of A9+ and A21 are not interchangeable. Though they share the same length-width, the the A21 battery is slightly thicker and the contacts of the battery are slightly offset so that it will not work if inserted into the A9+. More number of unique battery designs is generally not good for customers. If Karbonn stops making replacement batteries (don’t know if they even sell replacement batteries), customers would be left in the cold. It also appears that Karbonn’s support telephone numbers do not work.

The world has barely standardized on mobile-phone chargers. It is high-time that some sort of standardization occurs in battery design too.

Other Issues

Network

The A21 does seem to suffer a little more from network problems than the A9+. While my A9+ worked merrily throughout my house on the really poor BSNL network, the A21 behaved more normally and disconnected my calls half-way through the conversations. 😉

Chassis

While some buyers have complained of creaky back-cover and touch-screen issues when the phone is plugged in, I actually did not face these. The back-cover on my phone is snug and creak-free. The back-cover of my A9+ on the other hand is creaking.

At times the touch-screen exhibits the same problems that the A9+ does when it is plugged in. Yet at other times, the phone works perfectly. Looks like this phone too suffers from engineering issues with the touch screen and is not completely trouble free.

The micro-switches for Power and Volume Control are covered in a black plastic sheath on the A21. On the A9+, these micro-switches are exposed. Along with touch-screen issues, you may face issues with the volume control where the volume goes up/down as you use the touch screen.

If the touch screen becomes unresponsive and seems to misinterpret your touches, try to restart the phone. You will experience this problem more as you launch and close many applications. Restarting the phone fixes the issue.

Interestingly, the port of the USB charger is upside down in this phone. Please pay attention to this and insert the charger pin in the correct orientation. Forcibly inserting the charger in the incorrect orientation will for sure damage the socket permanently. The volume rocker keys too are on the right side of the phone (versus the left-side of the A9+ and most other phones).

Packaging

I had bad product delivery issues. Though the package arrived from FlipKart in record time and seemed unmolested. Upon opening the ‘sealed’ box of the phone, I found oily fingerprints all over the phone screen, oily smudges all over the battery compartment and a clearly re-sealed battery pack. I have a feeling that this is a Karbonn mobiles fault rather than FlipKart’s. Perhaps Karbonn has sold me a refurbished phone for the price of a new unit or perhaps Karbonn employees are not using hand-gloves during manufacturing / packaging of the product.

Also, the phone did not have a screen-guard installed and the box contained only one screen-guard. Other buyers have confirmed that their packages contained additional screen-guards. Maybe the person installing the screen-guard messed up and chose to simply pack the phone with one screen guard (uninstalled).

Camera

The phone features the exact same hardware as the A9+ in the imaging department. Consequently, images taken by the cameras are nearly identical. The resolution is barely acceptable. Dynamic range is poor. Focusing speed is acceptable but in low contrast scenes, it requires multiple attempts to focus the camera on the subject before taking the photograph.

I wish these cameras came with a tripod mount; even if it requires a new tripod mount size to be invented for small-size-light-weight cameras.

Performance

The phone’s hardware specifications are identical to the Karbonn A9+ and I did not expect too much variation in performance levels. In any case, here are the numbers: (Note that these scores vary marginally every time we run these benchmarks)

Sun Spider Browser Score: 1883.7 ms

(A9+ = 1940.3)

[table “16” not found /]

The phone comes preloaded with a couple of apps likes Yahoo Messenger, WeChat, PayTM, TimesOfIndia, Popi, nexGTV, WhatsApp. These apps cannot be removed from the phone without ‘rooting’ the phone. Some of these apps also start at boot time and eat up precious RAM (phone features 384MB RAM, RAM available after phone restart = 78 MB).

Should You Buy This Phone?

IMHO, the phone is good value for money. Touch-screen issues aside, the phone is usable much of the time and you will hard-pressed to find a phone with such specifications for 10.5K! Remember, there are worse offenders out there.

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