Osterburken sits in a Swabian-speaking corner of Baden-Württemberg, but Standard German (Hochdeutsch) is understood everywhere and is the right choice for visitors who do not speak the local Schwäbisch dialect. A handful of well-placed greetings and short questions covers nearly every interaction in this small market town, from the ticket counter at Osterburken Bahnhof to a Gasthaus table after a day in the Odenwald.
Because the town is rural and small, English is not universally spoken outside the tourism offices and the train station. Carry a few written phrases on your phone, use slow and clear Hochdeutsch, and you will get by comfortably in pensions, on Regionalbahn platforms, and when asking for the bill at a family-run restaurant.