Sencha Touch 2.0 Ext.navigation.View pop method really slow on iPhone
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We are building a cross-platform application with PhoneGap and Sencha Touch 2.0. 

The app is really light-weight, JS was compressed, nothing fancy is used and it runs  fine on Android phones. However, when running on iPhone4 the performances  are pretty bad. 

After several optimizations the app runs acceptable, except the back button (pop method from Ext.navigation.View), sometimes it takes 20 seconds or more to go back to the previous page. An example of 'previous page' where it hangs is a simple listing of elements that load from a javascript storage.

On the iPhone emulator everything works smooth.

Any help would be appreciated!