• Remotely unlocking doors, activating horn and lights and remote start for factory-equipped vehicles are among services General Motors said Wednesday it will make standard via smartphone for five years through the OnStar RemoteLink Mobile App.OnStar-equipped 2014 Chevrolet, Buick, GMC and Cadillac models will feature the service – even if the owner declines to pay for other OnStar services. It is the broadest deployment of remote services offered through a mobile app by any auto manufacturer.