I'm using the latest version of Spotify on my iPhone 5. This version is slower and unresponsive compared to earlier versions. When I click on a playlist or attempt to save a song to a playlist the app frequently takes a few seconds to respond. Sometimes it's 5+ seconds and I think the app has frozen up. Eventually the app advances, but this clunkiness makes for a very poor user experience.
Earlier versions of the app seemed lightning fast compared to this version.