Widgets in iOS are meant to provide data that is brief and meaningful at a glance. When lock screen widgets were announced, I quickly came up with the idea of this widget.
Simply put, it allows the user to pick which servers, and individual ports on each server, to test every time the widget becomes visible. Due to the limitations of the widget framework on iOS, it is not possible to run the checks on the background and send notifications to the user, but it still works well enough.
On top of that, there is a “Tap to Update” button that allows the user to manually check for the status of all servers.
This is my most popular app in the App Store, and I believe it is because it has a simple premise, and delivers on it well. It was a simple App to develop, but I don't think this diminishes its relevance at all.