After a view is navigated away from, it is hidden using CSS display: none. I don't think that destroying it would help a lot, but it may work in your particular case.
All view events are described in our API reference. The hide event in particular may be useful for disposing certain resources.
Our upcoming release will introduce a new event - 'afterShow', which will be triggered after the transition to the view is complete. A simple trick which may increase the app responsiveness is to hide the view complex contents (listviews with images, etc), and display them after the transition is complete.
the Telerik team
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