The application apparently crashed in iOS 5 due to the MKUserLocationBreadCrumb. Developer Will Strafach (Chronic) informed 9to5Mac that this API relates to the iOS maps and location functionality.
Just received the first iOS 5.0 crash report. MKUserLocationBreadCrumb sounds interesting.
Apple is expected to unveil iOS 5.0 at its WWDC 2011 Developer Conference.
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