For years, the southern portion of Shore Avenue area in Ship Bottom has been used as an alternate route, mostly by locals, for heading south on the Island via Barnegat Avenue to Central Avenue and finally the Boulevard as far south as 28th Street. That’s no longer true, and while it’s difficult to pinpoint exactly when the not-so super-secret backway onto LBI became more popular, one thing is certain: Navigation apps appear to control the fate of traffic on small, residential roads such as…