Copay is a free bitcoin-wallet app that uses multi-signature technology so that managing your Bitconis are a whole lot easier. This happens to be an open-source, beta app that will work in the same manner as that of Bitpay, which is the world’s leading Bitcoin-payment processor. Definitely useful in helping one manage a shared pool of Bitcoins alongside other people such as family members or business colleagues.
Since Copay would allow multiple people to access a Bitcoin wallet, and because of that, a transaction based on the parameters you choose could require more than just a single signature. Do bear in mind that the Copay app still remains in beta, so Bitpay recommends that you use it for smaller transactions, and try not to stash too many Bitcoins there. [Press Release]