Do any of the Zapworks samples demonstrate the Pokemon Go style of AR where a user doesn’t have to place an object in space (a la World Tracking) or do image tracking, but just have the object appear in the viewport on startup? Sorry, there’s probably a name for this style of interaction that I’m not familiar with.
I’d recommend checking out this post by Simon regarding Instant Tracking -
To summarise the advantages of instant tracking are:
Wide Device Support
Works in WebAR
Instant placement and WebAR are the two key takeaways when thinking about creating an experience you have described - instant tracking seems like the tracking type for you!
Hope this helps, let me know if you have any further questions.