I have read about Lighthouse a few months ago but I didn't realize it was already operational / usable. I guess I'll have to look again. I'm not sure if their "open source only" policy would apply here - the Android-based OtherCoin app will be open source, but the JavaCard-based secure component running on the secure element will not be. You will always need a secure element for the app to function (I have some medium-term plans to allow first time users to remotely access a secure element that we host in order to try the app before they buy the secure element, but that would negate the anonymity part, we would know who's accessing our hosted secure element).