It’s been a busy week for US streaming music service Lala, following news that it’s working with Google on a new music search service, and with Facebook on music gifting.Now Wired’s Epicenter blog is reporting that Lala is also working on its own iPhone application, which will tie in with its website. That means users who’ve paid 10 cents for unlimited streaming rights to a song will be able to stream it on iPhone too for no extra cost.The app will also provide access to users’ own libraries of music. It’s expected to be available by the end of the year – IF Apple approves it. Will it? Recent approvals of apps from Spotify and Rhapsody imply that Apple is fairly relaxed about letting streaming music apps onto the App Store – even from competitors.However, if Lala wants to let iPhone users pay for streaming rights from within the app, it could face problems. Currently, the minimum in-app payment that’s possible on iPhone is $0.99.