Phillybus rapidly displays real-time location information about SEPTA buses and trolleys operating above-ground.
Vehicle locations are obtained every 3 minutes. If a vehicle's signal is obstructed (for example, it's in a tunnel or blocked by a building), a polling can be missed. This is a limitation of the hardware on the buses, not in the app.
This app requires a network connection and relies on a data feed provided by SEPTA. This feed is generally reliable, but sometimes goes down.
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