Music app developers are continuing to explore the potential of tapping into the catalogue of streaming music services like Spotify, Rdio and Deezer via their mobile APIs. Two new Spotify-powered iPhone apps are in the news this week, taking different angles on location-based music. Tunaspot started life as an app within Spotify’s desktop client, and 100k users later is now on iPhone. The idea: playlists tagged to specific locations on a map, although the iPhone version can only find and play these playlists rather than do the actual tagging. Pow Wow is more about helping people create collaborative Spotify playlists in a particular location or event. For example, weddings or parties. One person with a Spotify premium account runs the app and creates a playlist, then invites friends (who don’t need a premium account but do need the app) to add songs. SoundCloud, Rdio and Deezer support may be added in the coming months.