An Advent calendar is used to count down the days before Christmas, where a person opens a window to reveal a small gift, chocolate, or poem. Each window represents a numbered day, and the windows are usually not displayed in any particular order. Advent calendars can be based on different themes ranging from traditional manger scenes to Santa Claus to your favourite sports team.
When looking at presenting features within a web map, particularly point features, there a few benefits that can be taken from this concept of opening little windows to reveal something special. First, by having information and media contained in a map pop-up, you are rewarding users for performing the actions required to explore the map. Second, the user has the freedom to explore as much or as little of the web map as they wish, making it a truly interactive experience. And third, the simplicity of presenting just a map and letting the features do the talking reduces the need for large amounts of supporting text as panels or sections.
Format your map pop-ups!
If your web map within an application is intended to be explored with information contained in the map pop-ups for features, then always be sure to format those pop-ups. A clear, concise listing of attributes or a nicely formatted paragraph of text and media, or even just media on its own, is a much nicer reward for your users to discover as opposed to a garbled mix of fields unrelated to the map's core theme.
Furthermore, if your web map has features not intended to be clicked on, then turn off pop-ups for that layer completely as users unintentionally finding "FID = 382" on a boundary polygon shown for visual reference detracts from their overall user experience.
Guide users with labels
Much like the numbered days shown on an Advent calendar, you can label features in your web map to help guide users if they wish to explore features sequentially, like by year.
By focusing on presenting information within map pop-ups, you can add value to your web mapping applications and story maps. While it may not seem as important as large paragraphs of text or high-resolution cover photos, it allows for your web maps to be truly interactive and enables them to take centre stage as opposed to playing a supporting role. If you intend for users to spend time on the web map components of your application, reward them!
More Information:
Learn more about configuring pop-ups in Map Viewer
Learn more about configuring pop-ups in Map Viewer Classic
Pop-ups: custom text display (ArcGIS Blog)