Glacier

Glacier secures your Bitcoins using multiple keys which are stored offline. This makes your keys virtually invulnerable to electronic theft while making sure that you can access your Bitcoins even if you lose one of the keys. Glacier doesn't depend on any service or third-party to store your Bitcoin keys. You can protect your keys without having to trust others or pay them any service fees. Glacier also provides different ways to store your keys offline, making it flexible. Glacier is open-source so that anyone can use it, reviewed it, and help make it safer. If you spot any weaknesses or vulnerabilities, you're welcome to contribute by opening pull requests or opening issues.