Taxis & Uber
If you need a taxi, know that you won't have to haggle with the driver because the meter will be turned on. It's obvious wisdom to double-check that the meter is turned on and functioning normally everywhere you go, but Germany is the country where you're least likely to encounter a scam taxi.
Uber is available in Berlin and Munich if you want to use a taxi app, but it simply orders you a taxi. You can also order a cab using the MyTaxi app. If you want to pay with a credit card in a taxi and aren't using an app that stores your credit card information, make sure you plan ahead.
A pos is not carried by every German cab driver. When I requested my hostel to arrange a taxi that accepted credit cards, I discovered this the hard way. Because this request was misunderstood, my taxi driver threatened to arrest me, and I had the worst Dresden tour experience of my entire trip.