Summary

Developer Timothy Lee found himself at odds with some of the privacy decisions being made at blockchain.info, which eventually led to his leaving and launching competing wallet Arcbit. And Arcbit has indeed broken some ground from the privacy perspective, as the first iOS wallet that supports Elliptic Curve Diffie-Hellman-Merkle (ECDHM) addresses, stealth addresses as they are better known.  The innovation was enough for ArcBit to achieve the fifth highest score on the Open Bitcoin Privacy Project, placing just behind DarkWallet and in front of Samurai Wallet.  An excellent showing for a very new wallet, which portends to great things moving forward.

Getting started

Stroll on over to the apple store and download the arcbit bitcoin wallet. As soon as it has downloaded, you are ready to start sending a receiving bitcoin – no registration of any sort is required. Though not mandated at the start, perhaps to avoid scaring off new users who seem to be targeted with this app, you will soon be confronted with a pop up window, which reminds you to record your backup terms – this can be done by clicking the “show backup passphrase” in the settings menu.

You will also notice the option to enable a four-digit pin code, which is recommended as protection in the case your phone is lost or stolen. The wallet may also be backed up in the icloud, though you will still need the mnemonic phrase and the wallet may only be restored on the same device. Not entirely sure why it is needed, but there it is.

Using the Wallet

When you first open the app, you’ll find yourself on the “receive” screen, which is set to default “account 1”. You’ll notice a large QR code with the long address written beneath. A click on the QR code will copy it to your clipboard allowing you to paste it in an email or SMS to request payment (or to send funds from your other wallet). There are seven different addresses set by default, the last of which is the “forwarding address”.

This forwarding address is what makes Arcbit unique. The forwarding address allows payers to derive a unique, one-time public address which is associated to the forwarding address – but nobody save the Arcbit wallet holder can ascertain the connection. This allows the forwarding address to be used as many times as required – which could prove quite valuable to, among others, website owners who wish to publish an address on their site for payments or donations without compromising on privacy. You can set forwarding addresses as default from the advanced setting menu.

New wallets can easily be made and organized through the “accounts” tab under the hamburger icon, allowing for users to organize their funds and payments into separate categories which cannot be connected by the outside world. Each new account contains its own initial addresses and change addresses, which are generated and cycled through as the current ones are used. And of course, each new account comes with it’s own forwarding address.

The send screen provides the option to choose from which account to send funds, and offers a scan QR code and address book tab. You may add contacts to the address book by scanning the associated QR code or pasting their address, after which you may label the contact at your convenience. Payments may be made in bitcoin or in the bitcoin equivalent of tons of different fiat currencies, which may be set in the settings menu.

Additional features

Arcbit is meant to appeal to new bitcoin users, but navigate to the settings tab to find a number of additional features available. While automatic fees are enabled by default at .0001, this may be adjusted which is quite important as bitcoin enters a new phase in which fees will play a more important role in getting transactions picked up by miners. Enabling “advanced mode” allows for the importing of private keys and watch-only addresses.

Bottom Line

ArcBit does an excellent job masking user transactions from the prying eyes of blockchain watchers.  They, like many other mobile apps, have been unable to crack the network privacy issue, to mask identities from ISPs and other snoops.  It will be interesting to see how/if the market, and ArcBit, are able to deal with this issue.

The product is extremely simple to set up and start using, and a good starting point for bitcoin novices.  The multiple address interface is perhaps a bit cumbersome, and would be perhaps be easier for some if addresses were auto-rotated without being displayed ahead of time, but this is nitpicking.  And of course, the more advanced users will be able to perform other tasks to which they might be inclined, such as integrating watch-only addresses associated to cold wallets or what have you.