Google is developing an experimental podcast app called Shortwave

An experimental unit within Google has been quietly developing a new app for discovering and playing podcasts. Called Shortwave, the new app was revealed by a trademark filing embedded below, which describes it as “allow[ing] users to search, access, and play digital audio files, and to share links to audio files.”
Nothing in the trademark filing specifies the kind of audio being accessed, but a Google representative said the focus of the app was on spoken word content. There is lit