One of the functionalities of the Google Search app widget is it'll also allow you to quickly search your installed apps, so you can type the name of the app and quickly access it.
It would be a nice feature to add to the Kagi Android app (widget) to have the same behavior. Personally I am very used to this workflow so I have left the Google search widget on my home screen to keep this ability.
When a user wants to open Instagram for example, they could tap the Kagi Search widget and start typing, "Insta" and Kagi would display it below the web search suggestions. Additionally, if they start typing the name of a website which they didn't realize they had the app installed, this functionality may help them get to the service where they want to go quicker.
Both Google and DuckDuckGo have this feature implemented. Google displays the app icons much like an app drawer, and DDG lists them out in a separate section.