People enjoy customized and personalized functionality — it helps them express themselves, feel unique, and be a part of the community. You can add customization to your UI by allowing users to change avatars, fonts, backgrounds, modes, or other elements.

Most designers believe customization is a powerful tool to encourage commitment and engagement. However, the dark side of customization is offering too many options. Users might find the idea of an indefinite number of choices appealing — but things change once they have to decide and pick one. User satisfaction level decreases with the number of available options.^[1]

Apple is an excellent example of adhering to the "less is more" principle. iPhone's customization options are minimal, which helps users make a selection faster and feel happier. Users don't want to see pages of available options — it frustrates them and leads to choice paralysis.^[2]