1, Availability: This seems a bit empty, but it makes sense. The application must be available before users can use it. If users think this APP is complicated, they will definitely not download it from the App Store. Usability will make the product useful, which is also the first step to success.

2, easy to operate: easy to operate is actually similar to usability. Every developer wants users to instinctively know how to use the interface, which is the use of design patterns. Familiar patterns can make users easily adapt to new applications. So in some cases, instead of a lot of innovation, it is better to adopt conservative design methods and let users scratch their heads.

3. Function and logo: logo is the prompt function of function. For example, the display of underlined blue text, users will know that clicking it will jump to other places. Using the correct logo, users don't have to spend time thinking about the purpose of each UI element, which saves users' time and also makes users feel good about your software.

4. Feedback and response time: Feedback lets users know whether the task is completed. It can be a simple buzzer or a more complex modal window. Please make sure that your comments are friendly and humanized, and guide users to the next step within a certain response time.

Designers should consider the above factors clearly before carrying out interactive design.