We're way ahead of you guys ;) On Mon, Feb 2, 2015 at 6:54 PM, Martin Habovštiak < martin.habovstiak@gmail.com> wrote: > Good idea. I think this could be even better: > > instead of using third party, send partially signed TX from computer > to smartphone. In case, you are paranoid, make 3oo5 address made of > two cold storage keys, one on desktop/laptop, one on smartphone, one > using third party. > https://www.bitcoinauthenticator.org/ - does this already, currently in alpha > > It should be possible to use multisig wallets to protect against > malware. For example, a user could generate a wallet with 3 keys and > require a transaction that has been signed by 2 of those keys. One key is > placed in cold storage and anther sent to a third-party. > BitGo, CryptoCorp and (slight variant) GreenAddress all offer this model.