Registration issues in Germany are handled at the Bürgeramt – Citizen Service Centers
Who needs to register and where
Do you plan to stay in the country for more than 90 days, have moved to another city, or simply changed apartments? Then you need to register at the Citizen Service Center (Bürgeramt). This must be done within two weeks after moving.
As Deutsche Welle notes, this rule does not apply to tourists, who do not need such a peculiar registration at all. Residents of Germany can obtain it, by the way, for several apartments at once and even in different cities simultaneously, but in some cities you have to pay a special tax for this (Zweitwohnungssteuer).
You can also register your residence at a new address online, but unfortunately, this service is not available everywhere. Since summer 2018, residents of Bonn can fill out a form in their personal account, attach scans of the necessary documents, and wait for confirmation. This is only possible if you are changing your address within Bonn and already have a password for your account on the authority's website.
However, only part of this procedure is done online: after receiving confirmation by email, you still have to go to the district office to get the registration certificate (Meldebestätigung).
In other cities, you can schedule an appointment yourself through the Citizen Service Center website. However, in metropolises like Berlin, Munich, or Frankfurt am Main, it is better not to try to find a free time slot in the authority's schedule. It is easier to sit in line, get a ticket, and submit the necessary documents. Registration by mail is impossible; without personal presence, only with a power of attorney.
What is needed for residence registration
To the Citizen Service Center you need to bring an identity document (for foreigners, a passport), a completed application form, and a rental agreement (Mietvertrag) or a confirmation from the landlord (Wohnungsgeberbestätigung). All forms can be found online.
Berlin has gone further. There is a special smartphone app, Berlin.de Service-App, which finds the nearest authority, shows all necessary information about making an appointment, and provides instructions on procedures.
Why German registration is needed
Registration is, in principle, mandatory for all residents of Germany. It may be needed when changing a passport, residence permit for foreign citizens, and so on. If you are registering in a city for the first time, you will likely receive a magazine with coupons for free visits to local attractions, museums, discounts at restaurants, etc. In addition, this brochure contains important information about the work of municipal institutions, the city's history, and significant places.
Besides such a pleasant surprise, after registering a new apartment, residents receive a notification from the Service Center for the license fee of ARD, ZDF, and Deutschlandradio that they need to pay the public broadcasting tax. Currently, its amount is 210 euros per year.