I use stereo Bluetooth headphones with both my iPhone and my Ipad now, and they work great! However, I noticed some apps do not play through the headphones and some do. For example, one of my favorite apps is "Looptastic" - a great music looping app. But the sound from the app goes through the internal iPad speaker even when my Bluetooth headphones are connected. On the other hand, most of my other apps do indeed play through the headphones (including other music apps). I was just wondering if this is a developer implementation or just an oddity I hadn't noticed before? I presume that the developer must have control via an API whether to allow Bluetooth output? A couple other apps that do not play through Bluetooth connection are "Magic Piano", Smule's piano app, and "Glee". However, there are plenty of other piano and synth apps that DO play through the Bluetooth. I wrote the developer of Looptastic a question about this. I am currently awaiting a response, but I thought you guys might know definitively?