Please refer to the support ticket you've opened regarding the same case.
In short, the reason for the memory consumption issue was that you're always calling NavigationService.Navigate
to swap between two pages. This will always
create a new instance of the corresponding page and put it on the back stack. Constantly doing this will always consume more and more memory until your app crashes. This will happen sooner or later depending on the UI complexity and the data stored within your pages. You need to use NavigationService.
for cases when you want to go to a page you've already visited.
I hope this helps.
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