https://crypto.stackexchange.com/questions/18091/is-there-any-true-anonymous-cryptocurrencies/18096#18096

He mentions DarkWallet a couple of times and discusses CoinJoin and CoinSwap at the start of his post both of which are proposed for DarkWallet. (Are they only using CoinJoin at the moment? Not sure...)

Also here is some information from the DarkWallet wiki:

https://wiki.unsystem.net/en/index.php/DarkWallet/CoinMixing