Introduced in 2017, the Google Play Security Reward Program offered up to $20,000 for discovering remote code execution bugs. However, this initiative allowed Google to collect data that is now used for automated checks, and since fewer malicious apps are being reported, this initiative will be terminated on August 31st.
Technically replaced by a similar product with a new name. I liked the simplicity of Chromecast, but if you bought the last two generations (anything past Chromecast Ultra) then you already have the more complicated device. So if you want to cast to a device, you can still do that.