What does your smartphone need in order to work?
Hardware and operating system
If you have ever used a computer, you'll be aware that a PC does not just consist of its hardware, i.e. its tangible parts. Every computer also has an operating system installed, which is a piece of core software that makes the device usable. The most well-known operating systems for PCs are Microsoft Windows and Apple OS X.
Other programs that specialise in different tasks such as word processing, graphics production or communication can then be installed on top of the foundation provided by the operating system.
You can think of the way a smartphone works as being similar, because a smartphone is simply a compact pocket computer. Every smartphone consists of hardware that an operating system is then installed on.
Programs are referred to as apps in the smartphone world. The most common operating systems for smartphones are ANDROID and iOS. iOS is used exclusively on Apple devices, such as iPhones, while Android is an open-source operating system and used on many different devices. This makes Android the most widespread operating system
Tariff and Network Operator
Now that you have your hardware, operating system and apps, your smartphone is in principle ready for use. To actually be able to make and receive phone calls and also use the Internet, however, you need a tariff with a network operator.
You can liken this to a car: Even a brand-new car with a full tank of petrol cannot go anywhere if it's in the middle of a forest. It needs roads. It's exactly the same with a phone: It requires a network operator's mobile network to be able to transmit data and phone conversations.