The following information may no longer be true, inputs service was hacked or owner scammed On November 7th, 2013 See https://bitcointalk.org/index.php?topic=248803.580 The article is kept only as historic documentation.
Inputs.io was a free Bitcoin eWallet that leveraged its own off chain payment network. Inputs was one of the most secure web wallets on the market, with two factor authentication, location based email confirmation, client sided hashing, and a setup that prevents the hack of Bitcoins even if the web server was compromised.
Inputs.io is no longer operational. On November 7th, 2013, the following message was displayed on the homepage: "Two hacks totalling about 4100 BTC have left Inputs.io unable to pay all user balances."
Database access was also obtained, email and passwords was stolen. Bitcoin backend code was stolen.
Users do not need to download the blockchain to create a wallet, which makes Bitcoin easier to use. Transactions are mixed by default with no fee to provide anonymity. However, the site doesn't leverage client side cryptography and doesn't allow it's users to export their private keys. Take caution when using any web wallet service.
Inputs.io also offers an extensive API for using the off-chain payment network.
Currently, Inputs.io is supported by the following sites:
Inputs.io is (was before hack) also a anonymous Bitcoin Foundation Silver member.