The default item renderers provide an abundance of customization options to display up to three children with a variety of layouts. However, sometimes, you need more children or more advanced layout capabilities to translate a design to code for a customized list. In those situations, you may need to create a custom item renderer class.
Custom item renderers are basically custom Feathers components. When you create a custom item renderer, you will be working at a low level inside the Feathers architecture. Ideally, you should understand the internals of Feathers components before proceeding.