GreenAddress is a leader in securing bitcoins and providing instant clearing confirmations. It supports desktop, mobile and web apps and offers a very featureful and secure wallet as well as APIs to enable third party developers.
GreenAddress: Instant and Secure Bitcoin
The presentation is introducing bitcoin’s multisignature features. These features allow users to radically improve the security of bitcoin wallets, as well as create new services like instant confirmation allowing for faster arbitration between exchanges.