After several months of experimenting with real-time tracking on its P1 East Busway route, the Port Authority will begin rolling out the technology on its website this month, giving riders the much clamored-for advance information about bus locations and projected arrival times.

The authority plans to launch real-time bus tracking on all of the county’s routes by the end of the year before turning its attention to integrating the technology with light rail. It will launch a tracker for the P3 route today, and the rest of the routes will be activated in groups of three to five after June 15.

“We’re going to turn them on in clusters to make sure there are no specific issues, rather than turn them all on at the same time,” says Port Authority spokesman Jim Ritchie. “We’re just taking the more cautious approach, but they’re all coming. The days of standing there not knowing what’s going on with a bus not showing up on time are over.”

Riders will be able to track buses through a new feature on the authority’s website which will refresh about every 30 seconds. The interface offers two views — one of estimated arrival times, the other of buses’ actual locations on a map.

The tracking system works on tablets and smart phones, and has a text-only version for users of other mobile devices. There’s no app for it right now, but that will likely change. As it activates the other routes, the Port Authority will reach out to third-party transit app developers which access and disseminate trip planning and arrival time information for transit systems in cities like New York and Chicago.

The stages that will unfold after this phase will fill in the gaps beyond just maps and arrival times, such as direct alerts to riders and information about why buses might be late.

“There are a lot of neat things coming down the road here,” Ritchie says.