A more thorough explanation:

Definition: The ultimate consumer for whom a product is designed.

Example: The person who buys and uses a smartphone is the end user.

This means that the end user is the person who actually uses the product or service. For example, a company may create a software program for businesses to use, but the end users of that program are the employees who use it on a daily basis. The end user is the target audience for the product or service, and their needs and preferences are taken into consideration during the design and development process.