An interesting question that many most will answer incorrectly. We spend majority of our time on smartphone. This puts smartphones at a much higher usage scale as compared to PCs.
The fact that smartphones are portable is perhaps the reason why people spend most of their spare time with it. In fact, this is also one of the biggest reason why it is crucial for small, medium and large enterprises to have a website which responds well on all form factors.
It is however worth noting that desktop systems are also very useful due to the fact that they have ergonomic capabilities that smartphones do not have. There is a limit to how much you can do on a smartphone. No matter how powerful a smartphone is, it still hasn’t reached a point where it can execute all the tasks that a very powerful pc or server will, such as intense graphic design or high resource demanding video processing.
A smartphone runs on battery. This is a major drawback as you cannot continuously run it without a charge, while this isn’t the case with desktop. A desktop has a full fledged keyboard which can be useful in tasks that require extensive writing.
It is also worth noting that if you consider the storage and upgrading factors, a smartphone cannot reach the capabilities of a desktop. Even though you may use a smartphone as a portable device, there are far more important reasons why a desktop system can never be replaced by a smartphone.