Frequently Asked Questions
- What currency exchange sources do you support?
- BitcoinAverage.com, BitStamp, Kraken, LocalBitcoins, The Rock Trading, BTC-E, Huobi, BTCChina, BitFinex and QuadrigaCX.
- Can I migrate easily from another wallet (like blockchain.info)? Can I sweep private keys funds into my wallet?
- Yes and yes, you can, just have a look in the Receive Money tab, put your private key in the right field and client side the funds will be swept into your wallet. Voilà!
- Can I try your service? Do you have a testnet/UAT version?
- Yes and yes, you can try our testnet version on test.greenaddress.it, gu5ke7a2aguwfqhz.onion and you can find a testnet faucet on tpfaucet.appspot.com.
Don't forget to send the testnet coins back to the faucet when you are done!
- Do you support other platforms than a web page?
- Yes! You can download an Android app from the Google Play store, an iOS App from the iTunes Store and a Chrome packaged app from the Chrome Web Store. All apps are open source and you can see the source code of each on GitHub. It also uses Electrum servers for additional transaction verification, so it should be safe to use even if our servers are compromised.
- But what happens if your service goes away? Will I lose my coins?
GreenAddress signs each transaction with its own key in addition to client-side signing by user's keys, and funds are stored in 2-of-2 multisignature outputs requiring both signatures to spend. The drawback of it is that you cannot control your funds without GreenAddress' signature, so you are right to worry that you can lose your coins.
But! We have solved this issue by providing nLockTime transactions which essentially make deposits 'expire' after some time, which allows redeeming them without our intervention after this pre-set period of time. It is enabled by default when you have email notifications and two factor enabled.
This allows you to keep your ease of mind even in case GreenAddress disappears with its keys.
It also means that every time the funds expire the user has to re-transfer them. This can be automated on login and notified in advance via email or manually done.
- How is your wallet better than the others out there?
For a simple high level comparison with a couple of web wallets please see this table.
We offer all the advantages of a web wallet:
- Ubiquitously available
- Two factor authentication
- Transaction limits/restrictions
- GreenAddress' third party trust instant transaction
And the advantages of a local software wallet like Electrum:
- Mnemonic seed backup once and forget
- Your private keys are never stored on our servers, not even encrypted
- No lost time synchronizing the client with the full Bitcoin blockchain
Simply put, we offer the best web wallet available: We include more features and security safeguards than the competition with a simple interface through your browser or phone.
- Where are my Bitcoin keys stored?
- Your keys are not stored. They are derived from your mnemonic passphrase and never sent to the server.
- How does the PIN work?
- A random password (256 AES) is created and used to encrypt your mnemonics and store them on your device in encrypted form. The random password is sent server side and destroyed on the client. When during login the user provides the right PIN a mechanism will ask the server for the password which is used to decrypt the mnemnonic passphrase stored on your device and get you in your wallet. If the PIN is provided wrong for 3 times in a row the password is then deleted from our servers.
- When are you going to offer feature XYZ? I would like to access my wallet in my language, can you add it?
We are constantly looking for feedback from our users, if you want to provide some feedback or get involved feel free to PM on reddit (/u/BitFast) or send us an email at firstname.lastname@example.org
We have many features and language support for many languages in the pipeline, please check with us if you want to be kept up to date with development and please be patient :)
- Do you have a donate button for linking to users payment URLs?
Sure have a look below (let us know if you have created one!).
- What exactly is an 'instant greenaddress transaction'?
- Do you have any API available for developers?
Yes! You can see our API documentation at GitHub Pages.
- Do you support tor?
- Do you have a guide for 2of3 recovery?
Yes! One is available here
Your transactions are protected by both your signature and by a signature we apply when we get your permission via two factor. With this protection, comes the fact that people receiving Bitcoin from you can trust the funds instantly as we provide a 'special' signature to your transaction when you require instant confirmation.