When choosing between different tablets from different manufacturers you will be confronted with lots of facts and figures.
In this article we will look at the basics and explain their significance and give some general pointers.
The version of Android that the device is currently running.
Since April 2009, Android versions have has a confectionery-themed code name, and a version number using a major.minor numbering system.
This Wiki article has a complete list of OS versions
Tablets for sale on Amazon tend to be running 4.1, 4.2, 4.3, (Jelly bean),4.4 (KitKat).5.0 (lollipop) as well as the latest version 6 (Marshmallow).
Major device manufacturers have a automatic upgrade process with updates automatically downloaded from the Internet, and installed automatically.
This is one of the big advantages of choosing a Google device (nexus range) as they will be the first to get updates.
Cheaper tablets do not have this infrastructure and you will need to do manual updates, if you can.
To find out what version your device is using go to Settings>System>About Tablet.
Android runs predominately on ARM processors , but you will also come across android devices using Intel chips.
All android Apps will run on ARM devices but not all will run on intel powered devices. See ARM vs Intel
Today dual core seems to be the minimum specification with quad core also very common.
However comparing processors requires that you understand more about the processor architecture.It is not simply a case of 4 cores is faster than 2.
For example ARM has claimed that the Cortex A15 (Nexus 10) 2 core is 40 percent more powerful than the quad core Cortex-A9 (Nexus 7).
You can also find ARM processor comparison charts on the ARM site
There are also some models that use the intel atom chip but they are the minority.
The working memory of your android is called Ram. Generally the more Ram the faster the device runs, especially when running multiple Apps.
Today (2015) the minimum for mid-range to top end devices is generally 2GB ( Nexus 7), but most devices pre 2013 were 1GB (old 2012 nexus 7).
Budget devices tend to only have 512MB.
I don’t believe it is possible to upgrade the memory.
This is used for storing your Apps, files,music etc and is equivalent to the hard drive on your PC.
How much you need will depend on the number of Apps you want to install and the amount of data- files, pictures, videos, music etc that you will store.
Some devices have external SD storage so that you can expand your system storage using an SD card.
If you run out of storage you will need to transfer files onto another device e,g your PC.
However tablets are really meant to use the cloud, and so it is common to store data and files on the Internet (cloud) rather than on your local hardware.
8MB is really the bare minimum and doesn’t allow much room for additional Apps.
Note 1: Apps Usually need to be installed on Internal storage, but some can be moved to external storage.
Note 2: Google drive is not considered external storage as far as App location is concerned.
3G/4G SIM Support
Many newer tablets support access to mobile 3G/4G phone networks.
This is very useful if you travel a lot and need Internet access. See Mobile data access
Screen sizes are measured across the diagonal,l and so a 10 inch screen isn’t 10 inches wide, which is what many people think.
The actual width of the screen will depend on the screen aspect ratio which describes the proportional relationship between its width and its height.
The images below show two examples. One using a 4:3 apsect ratio and the other a 16:9
For example, the Google Nexus 7 (7 inch screen) uses a 16:10 aspect ratio with a screen with of 6 inches and height of 3.6 inches.
This is the total number of pixels that the screen displays and is given in width and height.
For example the Google Nexus 7 (2012) is 1280×800 and the Nexus 10 (larger screen) has 2560×1600 pixels
The larger the screen the more pixels it needs to create a good image, and the more pixels the better the screen image.
See screen resolutions on Wiki for more details
Touch Screen Sensitivity
There are two technologies used in tablet screens-capacitive and resistive.
Resistive screens are more accurate but require a stylus or fingernail, whereas capacitive screens can be used with the bare finger.
Most modern tablets use a capacitive screen.
Many tablets come with dual cameras
Front facing camera – faces user on same side as screen and is primary use is for video calls. Lower resolution than rear facing camera usually between 1-2MP (mega pixels). 2MP is more than adequate.
Rear facing camera – On opposite side to screen and used for taking photos. Resolution varies considerable with 5MP considered adequate for good quality photos.
See Cnet article –Camera megapixels: Why more isn’t always better
More than megapixels – what really counts in a smartphone camera
Deciphering Product Descriptions.
If you go on to Amazon looking for a tablet you will see a bewildering array of features for each device. The main features are usually displayed prominently in the product title.
The diagram below is a quick guide to the important features:
Related Articles and Resources: