Curtis mentions the app 'Upswipz' in this episode. This app was created on the show Legends of Tomorrow, which is also part of the DC universe.
In this episode, Michael Emerson plays Cayden James, a sort of tech/hacking genius. In the show Person of Interest, he played a tech billionaire who created a piece of tech called The Machine for predicting crimes before they happen.
The Canary Cry can be heard on the opening credit sequence.