pgAdmin 4 has no prebuilt packages for Debian and its derivatives, so I have created this Alpine-based Docker image (~161 MB uncompressed) to get it up and running easily on my Linux Mint 18 box.
Note that pgAdmin will run in desktop mode (no multi-user and authentication).
Run:
docker run -d -p 5050:5050 --name pgadmin nphung/pgadmin
Then you can access pgAdmin at http://localhost:5050.
If you have a PostgreSQL instance running on the host and you want to connect the pgAdmin container to it, remember that you cannot use localhost in the Host field of pgAdmin's "Create server" dialog, because localhost there means the container itself. Use the host's IP instead, e.g. what you get from echo `ip -4 addr show scope global dev eth0 | grep inet | awk '{print \$2}' | cut -d / -f 1`.
pgAdmin's log, sessions and SQLite configuration database will be lost if you remove the container. To persist them, create a named volume and mount it to /home/pgadmin in the container, e.g.:
docker run -d -p 5050:5050 -v data:/home/pgadmin --name pgadmin nphung/pgadmin
Now you can remove the container when you are done with it, and next time you need pgAdmin, you can start a new one with the same volume option (-v data:/home/pgadmin) and everything will still be there (the servers you added etc.), assuming you did not remove the named volume.