Over 1 billion devices with Google Assistant have been sold worldwide. This service will allow your listeners to play your station through their Google smart device by saying "OK Google, ask your station name to play". We can also add a (Google synthesised) voice intro if desired.
If your station is listed on TuneIn, then your listeners may be able to listen to your station on Google Assistant already. However there are still a number of advantages to having your own Google Action. Firstly, if your station has the same or a similar name as another station then Tunein may end up sending your listeners to a completely different station! Also, TuneIn often plays and displays adverts to your listeners (especially on phones and tablets) and they also impose geo locking restrictions. On phones and tablets, if users don't already have TuneIn, they have to download it and sign up/sign into TuneIn which adds further steps for your listener to be able to tune in. Having your own Action will solve all of these issues and provide a better experience for your listeners. Having your own Action also increases your stations exposure as your Action will have its own page on the Google Action website. Finally, having your own Action allows you to have a customised voice intro if desired.