Well first of all it depends upon the current scenario of the market,features provided by the competitors , Currently their is craze of Nexus 5 and Samsung S5,while Sony Xperia Z2 is about to launch.
While buying mostly people look after
-battery life(power)
-Megapixel camera
- Resolution
-RAM
-Android Version
-GHz
Google's Android mobile operating system is an open-source platform that can be licensed and used by any smartphone or tablet manufacturer. This is the reason there are countless new Android-based devices hitting the marketing at a breakneck pace. This article will provide you with insight into choosing an Android phone that best suits your needs.
1.Select a cellular carrier that is currently carrying Android phones.
Some carriers may have a carrier-specific version of Android, which could ultimately impact your decision.
2.Decide between a multi-touch display, a traditional physical QWERTY keyboard, or a hybrid; this will greatly narrow down your search.
3.Decide on the size and quality of the screen.
4.Choosing a phone with the technology you require is key.
For example, if you would like to take high quality pictures, a device with a high mega-pixel camera is ideal. Likewise, if you'd like to use specific third-party peripherals, Bluetooth technology or integrated ports may be necessary.
5.Consider the memory capacity.
6.Consider the CPU (or processor) that the phone runs on.
This is very important, as a higher CPU operating frequency allows you to do heavier multitasking and assures quicker global phone responsiveness and operation.
7.Pick a device that supports what most carriers refer to as "multitasking".
This refers to the ability to use voice and data simultaneously. This is necessary to take advantage of the Android operating system's full capabilities.
8.Select a phone that meets your requirements in terms of weight and size.
9.Compare the battery talk time and standby stats.
10.Selecting a device that is capable of handling 4G technology is necessary to take advantage of 4G networks, which all carriers will be moving to soon.

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