Can see 'Devices available' on ipad but not on iphone

[bassplayerchris]

Hi - I have spotify running on both my iphone and my ipad, i am attempting to stream things on my chromecast. However, whilst on the ipad I get a 'devices available' option, on the iphone I do not. As an illustration, taking the following set of instructions: https://support.spotify.com/uk/learn-more/guides/#!/article/chromecast-steps-and-setup When i select the now playing screen on the iphone, I don't have a devices available option (though it appears on the previous status display), on the ipad I do.