GreenAddress.it Review (2015)

When I started out with Bitcoin, there was very little choice in the wallet department, but these days there are so many it can get quite confusing. Normally I simply recommend a wallet for beginners but these wallets are updated quite often making such recommendations only temporarily relevant. So here will hopefully be the first in a series of software wallet reviews, giving you an idea of what different Bitcoin wallets offer and helping you choose the one for you.

These reviews do not include “scores” but rather recommendations. Every wallet reviewed in this series will be reviewed because it’s good for something or someone, not because they are “the best” or “the worst” or somewhere in between.

Disclosure: I am familiar with the founder of GreenAddress.it and have hosted him while attending the BitcoinTLV conference in 2014. This has allowed me to get a closer look at GA.it from the perspective of the founder.

Platforms – Web, Desktop, Android, iOS

GreenAddress.it (or GA.it for short) is one of those wallets which is more than just an app. When you open a GA.it wallet, as with many other wallets, you’re actually creating a seed which can be reused and imported into any GA.it app (such as on your phone, browser, hardware wallet, etc). There is a browser version (no install required, available for all platforms) with all the features if you’re not too concerned about security. However when you open your wallet in your browser it will warn you of best security practices (as good wallets should), and will recommend downloading a locally installed app on Android, iOS, or your desktop using Chrome sandboxed extensions (supporting Windows, Mac and Linux). The desktop version requires that Chrome is installed, though doesn’t require actually using Chrome.

TL;DR – GA.it covers all the major platforms with locally installed apps and also offers a web version. That’s cross-platform compatibility in my book.

Private Keys – 2 of 2, trustless

GreenAddress is designed with the intention of offering a solution for 0-confirmation transactions by using “Green” addresses for sending. This means that any service or merchant that trusts GreenAddress can be sure that transactions sent via GA.it will not be double spent (and therefore spare you from waiting for confirmations). They do this by making their wallets use 2 of 2 multisig, you hold one key and GreenAddress.it holding the other key. GA.it cannot make transactions that you don’t approve of because you hold the other key.

Every time you make or recieve a transaction, GA.it will send you nTimeLock-ed signed transactions making it possible to recover your money even if GA.it suddenly disappears using an open source tool called Gentle. This makes the wallet trustless (thanks, malleability) however if GreenAddress.it ever does disappear it would require a little bit of engagement.

GA.it allows you to create 2 of 3 multisig accounts which allow you to hold 2 of the keys. This means GA.it cannot provide 0-confirmation transaction security, however it also allows you to have full control without nTimeLock-ed transactions and their tools (using electrum) and makes the wallet fully trustless. GA.it provides step by step guides precisely how to recover your wallet for each method.

TL;DR – You hold a private key and GA.it holds a private key, however it is trustless. Also possible to hold 2 of 3 private keys.

User Experience and Features

GA.it is fully featured with everything you’d expect from a wallet. Basic features include:

• Mnemonic seed (easy to write down for backup)
• PIN security
• Two-factor authentication (using Email, Authenticator, SMS or Phone)
• Automatic translation to local currency and decimal denomination (BTC, mBTC, bits, etc.)
• Separate accounting (allowing you to use separate “accounts” in the same wallet)
• Barcodes for sending/receiving as well as importing/exporting

Extra features (many are thanks to the 2 of 2 multisig model):

• Set spending limits: this allows to spend up to a limit before requiring two-factor authentication
• Connect to social accounts: this allows others to send you money without needing to share Bitcoin addresses, as well as activating a “watch only” mode using these accounts
• Payment URL: this allows you to create a link which can generate a Bitcoin address from your wallet; this is very useful for receiving tips or payments without needing to manually share Bitcoin addresses
• Instant transaction confirmation (only available for supporting services and merchants)

As far as UX, I have to admit that GA.it is a little weak on this front compared to other wallets. Sometimes it feels as if they offer too many features. The wallet doesn’t have a strong feel of aesthetic and comfort. The wallets for all the platforms are actually the same base, and when you move from one platform to the next it feels like the same exact wallet. The one exception is the “lite” version for Android aptly named GreenBits, which actually looks like a proper mobile wallet. It lacks all the features (which can still be easily accessed with the “full’ version) but it really is much more comfortable for mobile use and feels good.

I have but one small gripe with UX and that when you don’t have enough money for fees the wallet doesn’t help you – it simply says “not enough funds”. Most wallets will ask if you want to send a little less to make room for the fee à la Mycelium and even BC.info. It may be a small thing but I find these kinds of UX stuff to be important – so many many times I wanted to send the remainder of the change in my GA.it wallet and I had to guess how much to leave for the fee.

TL;DR – One of the most fully featured wallets out there, if you look around you’ll probably find more than you thought you’re looking for in a wallet. Feels like a full-time programmer built the app with only a part-time designer.

Summary

I think this wallet offers good features, good security and a slightly weak user experience. If you are looking where to keep the bulk of your “hot” coins (those not in cold storage) I would generally recommend GA.it. If you’re a paranoid type and you’re looking for complete and utter trustlessness you can use the 2 of 3 accounts and still get most of the features however you may consider other wallets (probably with strong multisig security). I usually don’t recommend this wallet for beginners because of the design aspect and the amount of time and effort it requires to open a wallet (30 seconds instead of 5 seconds for other simple wallets), and also because beginners don’t need or want all these features. However the combination of features and the mobile version of the wallet make this wallet one of my personal favorites.