Google is offering quite a little bonus for Chromecast users. They are giving Two Months free subscription of Spotify Premium and Google Play Music. This offer is valid until 15th September 2016 for both Chromecast and Chromecast Audio users as well as who buys the new device in this period.
For Now it seems that the offer is for US users only and the offer is only applied to new subscribers, so to avail the offer you have to make a new account, if you have used spotify in past. Moreover, The two free months of Spotify Premium will save you roughly $20 and three months of Google Play Music will save you around $30.
Spotify is offering free subscription until 15th Spetember 2016, But Google has extended its offer until December 31st. Both the offers are available to redeem on Google Chromecast Offer Page. If you want to buy a Chromecast in order to take advantage of this deal you’ll get $5 discount and just need to pay $30 for a Chromecast or Chromecast Audio.