Firstly thanks for your interest in our library. Bluetooth is something I’m looking into currently, admittedly only on the main windows platform right now but with an eye to supporting windows phone 8 at the same release. Android support should then be relatively simple to add after that as all these platforms support the necessary Bluetooth socket protocols. Bluetooth support is therefore in general on the horizon and if these platforms are what you require support on we can probably sort something out for you.
Alas for iOS this is not so simple as the Bluetooth APIs that Apple provide do not allow for easy bi-directional comms to a non-iOS device. There are APIs we could use but they all have various issues (either they are iOS to iOS only, can only be used to send data in one direction or require private APIs and thus apps will not get into the App store). Note that this is a problem that is to do with the choice of APIs Apple chose to expose and is not a limitation imposed by us or Xamarin. If you require bluetooth transfer between a windows machine and an iOS device things could therefore be tricky regardless of whether you use our library or not.
Your best option will probably depend on a few things. What specifically do you need comms wise? Do you need bi-directional transport between the windows machine and an iPad? Are you using an iPad 3/4 or does this have to work on a general iOS device? Does the iOS side need to get into the App store?
Basically we may be able to sort this out for you if it’s a make or break feature and if you will require a license. Otherwise it will most probably end up on the back burner though feel free to submit a feature request. We want to see how important people feel this is.
Sorry for the long post, this is unfortunately quite a complex issue. If you get back to me I’ll try and advise further and maybe we can help you.