There's been a whole lot of Sturm und Drang around apps which uses the iPhone's UDID to track users. We're getting reports of Apple banning apps which access UDID - although there's nothing official yet. Frankly, it's well overdue. Users want their privacy respected, app developers want to know if their advertising campaigns have been successful, and ad networks (like InMobi) want to make sure we're sending relevant adverts to users. UDID was the easiest way for people to do all of that - but it wasn't very respectful of privacy. So it's going - and good riddance to it. The new InMobi SDK 3.5 does away with UDID. It's in beta now, and should be available for you to download in early April. If you have any pending updates or new submissions, hang on for a bit and integrate with InMobi Ads SDK 3.5 as soon as it becomes available. Look for it in the publisher section of your InMobi account - we'll also announce it on this blog. And Twitter. And via email. And on the Developer Wiki. Trust me, you'll hear about it! So, what's replacing UDID? Primarily, we're looking at ODIN1 which completely avoids UDID. In addition, ODIN1 is only ever transmitted once it has been encrypted, so no one can spy on it. With upcoming releases of the SDK, we're going to be looking at better ways to protect users' privacy. We want to make sure that apps aren't leaking private information, and that customers can trust us. Got any questions? Stick them in the comments box.