The latest release from TheGenealogist contains over 10 million new individuals recorded in directories from the first two decades of the 20th Century. This virtual bookshelf stacked with volumes from the early 1900s to 1929 includes publications from all over the United Kingdom and Ireland. It includes more than 70 London directories, 42 from 1900 to 1940.
There’s a list of all the directories available from TheGenealogist at https://www.thegenealogist.co.uk/coverage/directories/#includes