This app was mentioned in 2 comments, with an average of 1.50 upvotes
I cannot test it myself, as I don't have an Android device, but it would be great if it would work with Last.fm by 1. scrobbling to your profile and 2. allow Last.fm radio stations play with Spotify as the playback source, as this does not work with the official Spotify Android app, only with their desktop client.
I just noticed your other Android app "Last.fm Listening Now!" where the description says it has "Automatic play on Spotify." So maybe this already works with this app?
Here's mine: Jason-costa Also, i made an app you guys might like: https://play.google.com/store/apps/details?id=com.lastfm.listening.now&hl=en