There are plenty of services that promise to keep your passwords safe, secure and synchronised across devices behind a single master password that you can remember, but Dashlane is a new service that does that, audits those passwords for strength, saves your form information for quick entry on new websites and even keeps track of the purchases you make with that information so you can see it all in one view -- one that's only available to you, not even Dashlane employees.
Dashlane has two major components. The first is a cloud-based password management and auditing tool, very similar to (but not as robust as) LastPass or 1Password. It does keep your passwords in the cloud and synchronised across devices, so if that's a dealbreaker for you, you won't like it. You can use Dashlane to log in to any site or service you use and even use its built-in password auditing tool to see the strength of your passwords and pick better ones.
The second is a form and purchase management service, where the information that you find yourself entering over and over again on multiple websites, like your address, phone number and credit card number are encrypted and stored so you can easily fill out new forms on new sites when you need to and check out when you make purchases. When you do make purchases at sites or with information you have saved in Dashlane, the app keeps track of your purchase history in an easy-to-search and filter interface, so you don't have to keep reciepts or look through bank or credit card statements to find a specific purchase.
If you read that and instantly worried about the security of all of that data, Dashlane's approach to securing the information you store and save is designed to put your mind at ease. The service encrypts all of your information -- all of it, including your form data, credit card and purchase information, and passwords -- locally and in the cloud and only decrypts the information with your master password, on an authorised device. Your master password, by the way, is something only you know, which means only you can decrypt the data, even if someone else has physical access to your machine (but it also means Dashlane can't reset your password for you -- they don't have it! If you have more security concerns, Dashlane has even published a whitepaper, available on their security page, describing the extent of their security measures.
Dashlane is currently in private beta, but the team has been kind enough to give us 3000 invites just for Lifehacker readers. If you're ready to give the service a try, sign up for an account using this link to get early access to the beta.