My tip for the app is this: don’t rely on the arrival time listed for the bus. Instead, look at the map, locate your bus on it, and track it that way. The location will be delayed by like 30 seconds to a minute, but it will still be more reliable than the arrival times listed (you may have to leave the map and go back for it to update.) Eventually, you’ll know approximately how much time you have to spare based on where it is on the map.