Hi @JaneClifton! - I'm sorry you are seeing some issues with your story on mobile devices. The issue is the map that is used in that section (e4dddab72f754daeb89ebbdc861de897)has almost 20 layers, and that map is used in consecutive slides, so all those layers are being loaded twice. For lightweight devices like phones, this many layers presents a resource issue and causes the mobile device browser to crash.
From what I can tell most of the layers aren't even visible in the story, but unfortunately, even if they are not visible, just having them in the map requires them to be loaded in some way, and this takes up significant memory resources.
I'd recommend creating new maps that contain only the essential layers for each slide in your sidecar section. Also, the way that map is designed is such that there are several sets of layers that could be combined. For example, there are four different layers of "stops." Normally when designing a map you'd have one layer for stops and symbolize them differently, based on attributes, if needed. This is also the case with service destinations and routes -- there are four separate layers for each. This arrangement may be required or helpful for other uses of this data, but for storytelling it is not following best practices for map design. Sometimes a map that is optimal for one purpose is not optimal for others.
Let me know if this is helpful and if you have any additional questions.
Owen Evans
Lead Product Engineer | StoryMaps