Bridgewalker: euro-denominated wallet for the Bitcoin economy[Now part of Hive!]

[BTC Books]

I advise you to support multiple exchanges as soon as possible.

And get your server/servers somewhere other than the US...

[1714831517]

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[1714831517]

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[1714831517]

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[mestar]

This thing is centralized in two places.  Kill the Bridgewalker servers, it dies, kill MtGox, it dies.

[the founder]

Only in the Bitcoin world would this:

You solved the problem

I think he did.

Turn into this:

I advise you to support multiple exchanges as soon as possible.

LOL!  Everyone is trying to protect the guy for solving a problem... this only happens here.  

If he was working with anything else,  made a computer 20% faster,  made his phone battery last 4 times longer,  if he found a way to convert dollars to gold, he'd be a hero (those Gold ATM's made headlines for months).

Instead he figures a way to convert dollars to bitcoins on the fly,  and the advice is to watch his back because the exchanges are going to shut him down.

[jav]

ONLY 1.5% oh boy. Thats only if you never actually use that $ balance...  if you ever actually transfer that in or out of gox to use is the real world, that % is larger than credit cards will ever be.

Not sure I follow, can you clarify what you mean exactly? The 1.5 % are in and out, so that already includes using it for something, like let's say shopping at bitcoinstore.com . Or are you talking about turning Bridgewalker-USD into actual bills in your hand? Then yes, that will probably require an extra cash out step somewhere with additional fees. And that's a good point - I personally would consider this an interesting benchmark: Person starts with a $20 bill, turns that into Bitcoin, and a couple of weeks later pays some merchant and the merchant has X amount of USD in his pocket at the end. What is the fee for that complete cycle? If the user keeps bitcoins for the couple of weeks there is pretty much no telling what he ends up with - the market might have moved in his favor or against him. With Bridgewalker that uncertainty is taken out of the equation, for an additional 1.5 %. With fees for acquiring bitcoins and then fees the merchant is paying to convert it back, we probably can not beat credit cards at this point. But I would like to think that we can at some point, if we continue to optimize at all of these points.

jav: are you considering to release the source code at some point?

I might release the Android client as open source at some point, but the server will probably stay closed source for the foreseeable future.

Secondly - this is how to get bitcoin into anyone's hands quickly and easily.  Every friend you've got:  "Install Bridgewalker and I'll send you that twenty...".

My thinking exactly! :-) And regarding that: Transfers between Bridgewalker users are instantaneous and free.

I advise you to support multiple exchanges as soon as possible.

It's mostly a question of liquidity. If market spread is very large all of the time, you end up not getting the best price when moving in and out of Bitcoin which can increase that "round trip fee" quite a bit. That's why I started out with Mt.Gox USD market which is quite liquid. I would like to offer a Euro version in the near future.

What about currency conversion?  What if I have two accounts with Gox; one in dollars and one in Francs, and I want to settle up with a Frenchman?  Can I send my dollars to your server and have them come out as Francs on the other person's phone?

At the moment your Bridgewalker account will always be denominated in USD, you can not change that. But in theory there could be a separate Euro version of Bridgewalker (and hopefully will be at some point) and then you could definitely exchange money between the two. It would use Bitcoin as the middle man: Bridgewalker-USD -> BTC -> Bridgewalker-EUR.

And get your server/servers somewhere other than the US...

The Bridgewalker server is currently hosted in Germany.

[BTC Books]

I've got this installed, put in a small amount of BTC, and all appears good.  I'll be transferring money with someone else tomorrow.

[MPOE-PR]

The model seems incredibly dangerous because of volatility and slippage.

[Technomage]

Very interesting idea. If this actually works with low fees and it's possible to get this to work elsewhere with other currencies than the dollar, it could be a killer app for a lot of things.

[harningt]

What are the methods for getting cash in and out?

[jav]

The model seems incredibly dangerous because of volatility and slippage.

You mean dangerous for the users? I am not sure I would call it "dangerous", but yes, the risk of slippage is assumed by the user. That's why the 1.5 % round trip fee is typical, not guaranteed. If you happen to use it in the middle of a crash you will probably end up paying more. That's why Bridgewalker always gives you an estimation on how high the currency conversion overhead is.

So as one of screenshots show, if I enter 5 USD, I see something like this: "Recipient will receive 0.10991995 BTC (~ 5.00 USD). From your account 5.03004 USD will be deducted. This is a difference of about 0.6 %". So in this case you paying 0.6 % more than the recipient will receive. And market spread is already taken into account here, because for the recipient a market order sell is assumed (albeit without any exchange fess the recipient might pay) and for you a market order buy for acquiring the bitcoins plus exchange fees is assumed. If there happens to be a much larger gap, you will see this percentage value going up and might want to wait for the markets to settle before doing your transaction. But in my testing over the last months this hasn't really been a problem for me.

What are the methods for getting cash in and out?

Only Bitcoin.

[romerun]

why not using mtgox the polling data feed, it's super solid comparing to that shady streaming channel. The lag is unnoticeable most of the time.

[alir]

The link to your forum profile is broken. You have it set to the logged in users profile.

For your profile specifically, you just need to append ";u=4070" at the end of "https://bitcointalk.org/index.php?action=profile".

[davos]

I'm not sure if there's been much in the way of chargeback/attack security testing on the Giftcoins.me cards yet - but you might consider something along those lines (or just linking out to resellers) to provide initial and simple BTC acquisition for public users who want to explore the network and for whom a USD denominated account makes more sense.

You could even provide an in-app system for linking to bitcoin retailers (and probably derive some additional revenue that way) which would enable users quick access to the bitcoin marketplace. If they have a wallet on their phone with $xxx.xx USD in it and it is their primary or exclusive access point to the btc network they may find the fact that they can save hugely on bitcoinstore (for example) and only ever experience the transaction in USD (or at least have the USD price on every page of their transaction).

[jav]

why not using mtgox the polling data feed, it's super solid comparing to that shady streaming channel. The lag is unnoticeable most of the time.

Yes, good point, I might have to do that, if all else fails. I would just prefer to have real-time updates. Mt.Gox seems to work on a new version of their Socket.IO server, maybe that will improve things.

The link to your forum profile is broken. You have it set to the logged in users profile.

Aw, thx for pointing that out, I will fix it in next update.

I'm not sure if there's been much in the way of chargeback/attack security testing on the Giftcoins.me cards yet - but you might consider something along those lines (or just linking out to resellers) to provide initial and simple BTC acquisition for public users who want to explore the network and for whom a USD denominated account makes more sense.

That's definitely something I find very interesting: Go into the next supermarket, buy a Bitcoin gift card denominated in USD ("$20 worth of bitcoins, for $20.25), load that up in Bridgewalker (with the added benefit of checking that you got your money's worth) and then spend it next door on cupcakes or on they other side of the globe on candy from Japan. And as mentioned before, I would consider it a goal to get that complete cycle down to 3 % and lower to be able to compete with credit cards. (At the moment I find all these "Bitcoin has low fees" claims a little bit dishonest. Yes, Bitcoin transactions themselves are fairly cheap, but pretty much anything practical you will do with Bitcoins _today_ will involve some currency conversion steps, which are unfortunately not cheap yet.)

And by the way: Anytime Bitcoin gift cards come up, some people want to have them denominated in BTC. While that seems natural, I don't see how it would be practical at all. A supermarket etc. can not reprice items in their inventory every few days. It needs to be a fixed price for the supermarket and then some extra activation step where the actual conversion at current market price happens. Giftcoins.me got that part right and it is a very interesting project.

[amincd]

Perhaps Expensify could recommend Bridgewalker to their clients' contractors:

http://techcrunch.com/2013/03/27/expensify-now-offers-support-for-bitcoin-an-alternative-to-paypal-for-international-contractors/

http://help.expensify.com/bitcoin/

[simonk83]

So, iOS.   I understand your reluctance, what with Apple being the closed minded way they are, however..... Cydia     There'd still be a decent market (in fact I'd suggest the people who are into Bitcoin at this "early" stage are the same who'd have a jailbroken phone).

Anyway, just food for thought.

[jav]

So, iOS.   I understand your reluctance, what with Apple being the closed minded way they are, however..... Cydia

My impression is, that almost nobody actually bothers to jailbreak their device, even among those people who would be able to do it. So I don't know, it seems to me like that would be a very limited group of people to whom that would be a solution. But I'll keep it in mind!

@BitPay: A new version of the app is out which now completes the support for URI links - i.e. it also works now, when clicking a link somewhere. So that means all "must have"s according to lovebitcoins.org (which, by the way, is down at the moment (?) ) are present. :-)

[jav]

Quick update: I implemented a workaround to get rid of of the minimum limit of 0.01 BTC. Transactions down to 1 satoshi are now supported.

[jav]

Version 0.4 of the app is out now and I have updated the website. I have slightly pivoted in how the idea and the service is presented. The new description reads like this:

Bridgewalker is an exchange rate adjusted Bitcoin wallet. Your balance with Bridgewalker will automatically be adjusted upwards, if Bitcoin's exchange rate drops. Conversely, since there is no free lunch, your balance is reduced if the exchange rate rises. The effect is, that your balance stays stable in respect to the counter currency - currently USD. If you deposit $20 worth of bitcoins, Bridgewalker will ensure that you continue to have $20 worth of bitcoins, regardless of how the exchange rate develops.

Essentially I show your balance in BTC at all times to make it clear that this is really a Bitcoin wallet: Bitcoin in, Bitcoin balance, Bitcoin out. But that Bitcoin balance is adjusted up and down to create that "stable in respect to a counter currency" effect of the original Bridgewalker. It is really just a change in presentation, as the underlying system still works the same. But I'm hoping this presentation might make it easier for people to understand the value proposition and why such a service might be useful in some cases.

What do you guys think? I call it "exchange rate adjusted Bitcoin wallet" - does that term make sense to you? any better alternatives?

[jav]

Discussion continues here: https://bitcointalk.org/index.php?topic=228535.0

[jav]

Discussion continues here: https://bitcointalk.org/index.php?topic=228535.0

Scratch that, discussion continues here. ;-)

I have quietly continued working on this, mostly fixing some smaller bugs and increasing stability and robustness of the software system. Some updates:

• I switched from USD to EUR as the counter currency for the time being. As I'm based in Germany and I wanted to focus more on in-person use cases, it makes it more practical for me to prototype it. Sorry to anyone who was relying on USD accounts! I hope to bring back USD and add other currencies at some point in the future.
• Uploaded an old presentation that I gave about green addresses (there called marker addresses): http://www.youtube.com/watch?v=1iLV9zjxHFU . Bridgewalker has support for green addresses, so deposits coming from recognized green addresses are credited instantaneously.
• I put together a video demonstrating the app. It is online at http://www.youtube.com/watch?v=ERVD1xoDT0M - although unfortunately already outdated again. =)
• Implemented preliminary backup functionality for guest accounts.

And Bridgewalker is now also on Twitter: https://www.twitter.com/bridgewalkerapp .

As always: Feedback and comments much appreciated! :-)