There's a reason why the new Frankfurt old town around the dome is one of the post popular tourist spots in all of Frankfurt - the picturesque quarter dates back to medieval times, featuring intricate house fronts and even the remains of an old Roman residence.
The "New Old Town Frankfurt AR" app not only lets you explore old town from anywhere, but also features interesting tid-bits about the history of six different locations there, with accompanying video footage. To start your virtual visit, all you need are this app, the free AR postcard and an AR ready smartphone (requires iOS 11 or higher). Of course, you can also use it to prepare for your next visit in Frankfurt.
Have fun, and see you soon!