Hi @SimonLaughton -- Thanks for sharing your feedback! We do have adding the ability to show the live embed on small screen devices in our pipeline for 2022.
This feature, however, will generally work best when used with very simple embeds that still look and/or behave well in a small frame such as a tweet or Instagram post, a basic interactive chart, a single dashboard widget, or possibly a survey form. I'm skeptical that forcing a Web AppBuilder app—or any other type of GIS application—to load live in a small embed frame on a small screen will provide a good experience for your readers.
In most cases, the options that are already available are already the best available options for web mapping apps: show as a card or show as an image. In terms of how these options work across a variety of screen sizes, the live embed is be shown when a reader looks at your story on a desktop monitor, laptop, or a tablet in landscape orientation. The card/image is be shown on tablet portrait and phone screens. Both the card and image have the option to click/tap to open the app in a new browser tab, so the live app is always available for the reader to use in a full-screen capacity, it's just not embedded inside the story itself.
We're also looking at adding the ability to include a layer widget with a map without the need to use an app. But typically we recommend using map actions and map choreography since these two techniques allow you to create a much more directed, valuable experience for your readers that simply turning them loose with a layer list.
Unless your audience is made up of GIS professionals and/or very familiar with your story's topic, they usually appreciate being provided with the map views and layer combinations that help tell your story rather than being required to explore them to get anything out of your map. Even if StoryMaps does get a layer widget in the future, I would guess there will be differences or limitations to how it works on phones since there are simply more space constraints on small screens. Our designers are amazing, but they can't make phone screens any bigger. 😉 Map actions/choreography are two solutions we already offer that help optimize map manipulation to be much easier and more valuable for readers and work well on all screen sizes.
Hope this is helpful! Let me know if you have additional questions.
Owen Evans
Lead Product Engineer | StoryMaps
