In Germany the use of cash (€) is very common. Most of the times you will be able to pay by card, but it is safe to always have some cash available.
Germany is mostly an Uber-free zone, only regular taxis officially exist.
On Tuesday (2024-07-09, Munich) and Wednesday (2024-07-10, Dortmund) there will be the semifinals and on Sunday (2024-07-14, Berlin) the final of the European Football Championship in Germany.