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The application currently exits the app completely when the user closes the app or navigates to another app (like the native map). This was due to iOS memory issues causing the app UI to degrade after opening up other apps that require a lot of memory. The newer Titanium SDKs claim to have better memory management, so it may require little effort to implement. Otherwise, the app should save the state (what portlet is opened, and what data is being viewed) as the app is used, and restore to that state when the app is opened again.
Native App Framework
The uMobile project should re-evaluate Phonegap's capabilities. Phonegap could be used as a lightweight wrapper around the browser-based client to provide native apps for Blackberry and Windows phones. It may also be wise to re-evaluate Phonegap vs. Titanium Appcelerator.
UX Enhancements
Navigation
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