HomeKit accessories offer a lot of information and services that allow you to control your home. At times, they contain even too much. Often the information isn't helpful, or it's only useful in the vendor's proprietary app. With Aliases and Property Hiding, you can decide what information you want to see.
Sometimes accessories include very relevant information with very unhelpful names. If a manufacturer doesn't offer a display name for their custom characteristics and services, you will see the name "custom" or a technical identifier in the app. You can give these characteristics and services an alias to change how Controller will display them.
Many devices have characteristics that are relevant for the HomeKit framework but not for you. These are annoying because they take your attention away from the actual important information. Controller lets you hide the characteristics that you don't need.
Similar to characteristics, you can hide complete services if you don't want to see them every time you use the app.