So when does it make sense to make a single page web application? Are there any guidelines you folks like to follow?
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Traditional SPA
Those two I'm pretty sure what I would use, but the other applications in between those extremes I'm not that sure...Google Maps is probably a much better example.
The time I finish the app, I will tweak and optimize loading either by AJAX or implement something like backbone views.
Now we're building a mobile version, and having built the API in the first phase, we've got enough to go on to do it all via Backbone.
Additionally, when developing for mobile you're much more aware of bandwidth restrictions, so the ability to load only what you need becomes useful. When you're flicking through a bunch of pages that use the same view but with different data, an SPA lets you load only what you need.