Because I recently did a review on GreenBits I decided to do do a review on their other wallet product GreenAddress. I know the first question I’m going to be asked is why I would be recommending a web wallet when I’ve railed against them so hard in the past. You see, GreenAddress isn’t really a web wallet. Let’s take a look.
GreenAddress offers a per-transaction two factor authentication, multi-signature and deterministic wallet that never stores your private keys on their servers, even in encrypted form. At the same time it allows you to easily view and transfer your funds. They also have a watch-only mode so you can quickly check your balance or receive funds without full access to your wallet. This means you could safely check your balance and transactions from public Wi-Fi or an untrusted computer using this method. You can do all this from the GreenAddress webpage.
Although GreenAddress is available as a webpage, it is safer and more secure to run GreenAddress by installing the Chrome extension or by installing one of the apps. One thing I could say a lot during this review is that certain features are just like GreenBits. Indeed, they both use the same API, which means they’re very similar in form and function. But imagine that GreenBits is the sleek, lightweight version and GreenAddress is the flagship powerhouse. GreenAddress is everything that GreenBits is and more. Because of this I’m going to refer you to my original GreenBits review and focus here on things that I should add, such as thing GreenAddress has in addition to their other offering. If you want an app, I highly recommend looking at GreenBits instead. Because of that, this review is mainly on the Chrome extension and the webpage.
Install was as simple as finding it in the Chrome Web Store and clicking install.
I opened it up and was asked to enter my mnemonic passphrase so it could create my wallet. In the upper right hand corner it offers the choice to start a wallet if you don’t have one or, I’m assuming, if you want a new one. I chose to enter my old one. And here’s where I can show you that the backups work. Apparently I’ve used GreenAddress before writing this review and totally forgot.
I put in my old mnemonic passphrase that I found in my password wallet. It recreated my old GreenAddress wallet. It shows that I have transactions from 2015 and there’s still $0.30 worth of bitcoin in here. But before we get to anything important, I need to get rid of those two warnings at the top: setting up 2FA and verifying I’ve written down my mnemonic. I apparently didn’t do this in 2015 when I set it up.
As you can probably tell by the scroll bar on the right, the list of settings in GreenAddress is much more extensive than the one in GreenBits. Again, some features are the same, but GreenAddress adds much more.
For instance, whereas in GreenBits you can pull up your mnemonic phrase again to write it down, in GreenAddress you can do that, or you can show it in encrypted form, or even write it to a hardware wallet.
If you simply display it, it shows up as a QR code, as well as a list of words. This would make it much easier to log in in the future. Go back and look at the screenshot in which I entered my mnemonic passphrase. There’s an option to log using a QR code.
Unlike Airbitz, however, this isn’t a per transaction limit. It’s like a gas tank. It depletes with every transaction. Once it’s depleted you’ll have to verify until you refill it.
I know I’ve mentioned often that I dislike web wallets. I also know that I mentioned in my GreenBits review that I distrust the idea of storing with 2-of-2 multi-sig wallets. GreenAddress mentions in their FAQ that there is nothing to fear because deposits “expire” after some time. This is made possible using nLockTime.
nLockTime is a feature that makes it so that GreenAddress’s signature isn’t needed to sign transactions after a certain number of blocks have passed since the funds were sent there. This is a number which you can set, in order to feel comfortable. However, know that this means you must transfer your funds every time the nLockTime you set expires and transactions cost money.
If GreenAddress disappears or their service gets taken down, just know that you can wait until the nLockTime expires and then use their open source tool called Gentle, available on Git, to recover your funds.
But if even that isn’t enough comfort in security. Know that you can create your own 2-of-3 multi-sig wallets that will allow you to recover your funds without any kind of GreenAddress involvement, wait time, or special tool. It simply uses an import feature in Electrum, another Bitcoin wallet.
Which allows you to view transactions, receive, or view your address book. Basically, anything but send bitcoin or change settings. Because your private keys are never derived, this makes it safe to check in without fear of someone getting access to your funds.
There is a section in the settings that talks about being able to set it so that people can send you bitcoin using your email, Facebook name, or Reddit username, but I’ve not figured out how to use any of them. I’m wondering if this feature was never fully realized, but I can’t be certain.
The last feature I want to point out is one I mentioned in passing above: the Address Book. Now, I’ve repeatedly mentioned how I’m not a big fan of using addresses over, so I’m not a fan of this feature as it sits. I could, however, see this as an exciting feature if it incorporated BIP 47 addresses, or reusable payment codes. Then handing out to people so they can routinely send you money securely would be feasible.
Other than that, GreenAddress is very much like any other wallet. It sends and receives. It keeps track of private keys and transactions. It’s a very solid offering and one worth looking into if you’re a privacy minded individual and want to transact from your desktop. I could especially see using GreenAddress as your main bank at home and using GreenBits as your travelling wallet. I think they’d work very well together. I give them both a recommendation.