The aim of this guide is to help you decide which (smart-)phone is the best for you, based on your needs and budget.
Here are some basic points you should know when buying a smartphone:
1) Operating system (OS) - The user interface which allows common users to use the hardware components (camera, speakers, etc.). The most common operating systems which run on smartphones are:
Note that not all devices can be upgraded to the latest OS version. It's mentioned in the solutions listed below.
2) CPU (Central Processing Unit, or Processor, or the "brain" of a smartphone) - The main component of a smartphone which is a crucial factor for phone speed (how quickly applications open etc.).
There are several types of processors used in smartphones:
Note: You should treat the smartphone as a whole, as unity of all the components in it. It doesn't mean that a device which has an Octa-Core processor is faster than a device which has a Quad-Core processor. For instance, iPhone 6s has a Dual-Core processor, but it doesn't lag as much as some Octa-Core-processor smartphones.
The above-mentioned note also applies to camera quality. It doesn't mean that a 21 megapixel camera will produce higher-quality images than an 8 megapixel one (take iPhones for example. iPhone 6s has a 12 MP camera and produces better images than smartphones with 21 megapixel camera).
3) RAM (Random Access Memory) - The more RAM the more applications you can run in parallel. Usually, the amount of RAM in smartphones varies from 1 GB to 4 GB.
4) Storage size - The space you have to store your pictures, music, videos or other documents. The amount of free memory on smartphones varies from 4 GB - 128 GB of internal memory, plus the ability to add a microSD card (up to 256 GB)