Bitcoin Wallet for Android

[barbarousrelic]

From the perspective of the Bitcoin network if you receive 10 coins, wait for 6 confirmations and then send 0.1 coins somewhere else, what actually happened behind the scenes is that you received a new payment of 9.9 coins back to yourself (as "change"). So it's correct that it's unconfirmed.

Does the bitcoin.org client behave in this way?

[1714181063]

1714181063

[1714181063]

1714181063

[1714181063]

1714181063

[1714181063]

1714181063

[1714181063]

1714181063

[Syke]

Is there a way to import your own private key?

Thanks so much!  

Edit: I'm not seeing how we are supposed to import our private key. Do I need to save it as some type of file?

Use the export feature to get the existing key file. Decrypt it. Add your private key to the file. Encrypt it. Use the import feature.

Read the README for how to decrypt it:

http://code.google.com/p/bitcoin-wallet/source/browse/wallet/README

[jim618]

From the perspective of the Bitcoin network if you receive 10 coins, wait for 6 confirmations and then send 0.1 coins somewhere else, what actually happened behind the scenes is that you received a new payment of 9.9 coins back to yourself (as "change"). So it's correct that it's unconfirmed.

Does the bitcoin.org client behave in this way?

There is a difference between a transaction being confirmed and being spendable.
With the Satoshi client if someone else sends you bitcoin it is both unconfirmed and unspendable until it appears in a block. With Satoshi, your change is unconfirmed but is spendable straight away.

What Mike mentioned is to change the bitcoinj spending policy so that your own change is spendable. It is still unconfirmed though (meaning literally not on a block yet). This will then be the same as the Satoshi client.

Different clients have different spending policies and they change over time. I notice for instance that the 'old' Instawallet allowed you to always spend (even unconfirmed receipts from other people) but the 'new' Instawallet requires one confirmation. They allow you to spend your change immediately. I think that combination will become the norm.

[caveden]

I see no reason to forbid someone from spending an unconfirmed transaction, even if it's not change. Particularly now that bitcoind will soon be able to sum up all transaction fees in an unconfirmed transaction chain. If you are on the tip of such chain, just add a fee to it.

[Yuhfhrh]

Is there a way to import your own private key?

Thanks so much!  

Edit: I'm not seeing how we are supposed to import our private key. Do I need to save it as some type of file?

Use the export feature to get the existing key file. Decrypt it. Add your private key to the file. Encrypt it. Use the import feature.

Read the README for how to decrypt it:

http://code.google.com/p/bitcoin-wallet/source/browse/wallet/README

Thanks, but its way over my head. I don't even know where/how to start with "You can OpenSSL to decrypt:

openssl enc -d -aes-256-cbc -a -in <filename>"

[barbarousrelic]

From the perspective of the Bitcoin network if you receive 10 coins, wait for 6 confirmations and then send 0.1 coins somewhere else, what actually happened behind the scenes is that you received a new payment of 9.9 coins back to yourself (as "change"). So it's correct that it's unconfirmed.

Does the bitcoin.org client behave in this way?

There is a difference between a transaction being confirmed and being spendable.
With the Satoshi client if someone else sends you bitcoin it is both unconfirmed and unspendable until it appears in a block. With Satoshi, your change is unconfirmed but is spendable straight away.

What Mike mentioned is to change the bitcoinj spending policy so that your own change is spendable. It is still unconfirmed though (meaning literally not on a block yet). This will then be the same as the Satoshi client.

Different clients have different spending policies and they change over time. I notice for instance that the 'old' Instawallet allowed you to always spend (even unconfirmed receipts from other people) but the 'new' Instawallet requires one confirmation. They allow you to spend your change immediately. I think that combination will become the norm.

Thanks for the clarification. I get it now.

[Andreas Schildbach]

What are the timestamps in the keys-file? Are they necessary?

The timestamps are the date of the private key created, or the first appearance of the corresponding address in the block chain.

They are optional and are meant only for the importer to be able to catch-up the blockchain faster. If you leave it out, the whole blockchain needs to be scanned for the imported key(s).

[Andreas Schildbach]

Maybe a nice feature would be to be able to import private keys trough qr-codes

This is a planned feature. However for this to be secure, I need to integrate the QR code scanner into the app rather than relying on an external app plus the Android Intent system to securely transmit data. I'm working on it.

Also, can you give me examples of existing Bitcoin apps/web pages that export private keys via QR? Which format(s) do they use?

[jim618]

I see no reason to forbid someone from spending an unconfirmed transaction, even if it's not change. Particularly now that bitcoind will soon be able to sum up all transaction fees in an unconfirmed transaction chain. If you are on the tip of such chain, just add a fee to it.

Bitcoin Wallet for Android (BWA) and multibit are the same in this respect: they do not have access to all of the blockchain's unspent transaction outputs. They only know about their wallet's private keys. In this situation you do not want to consider an unconfirmed transaction as being valid at all. It could very well be a load of old rubbish. Once it is confirmed then you know that the bitcoinds out there believe it is real and hence you can believe it is real.

If you allowed unconfirmed transactions to be spent (for BWA and multibit I mean), you would just end up creating invalid transactions that would not even get propagated from the first node you sent it to.

[Andreas Schildbach]

I'm not sure if this has been addressed, but I think I accidentally sent bitcoins to an old address I had with this app. I have the prodnet.wallet fileand I was wondering how I can import the keys now that it uses a different wallet file.

If your wallet file is really named like you said, the wallet was not created by Bitcoin Wallet but by a different app (Bitcoin Android). It's not being maintained any more and uses a very old version of bitcoinj.

You can try this guide to extract your private key(s):

http://gary-rowe.com/agilestack/2011/12/28/how-to-recover-lost-bitcoins-from-an-android-wallet/

[Andreas Schildbach]

I have a tablet with BlackBerry Playbook system and I really would like to run Bitcoin Wallet app on it.
It's possible to repackage Android apps to BlackBerry App World, see: http://developer.blackberry.com/android/documentation/Mastertopic_1849583_11.html

Just today I uploaded a Blackberry test version:

http://code.google.com/p/bitcoin-wallet/downloads/list

Let me know if its installable on a Playbook and how it performs.

[Jouke]

Maybe a nice feature would be to be able to import private keys trough qr-codes

This is a planned feature. However for this to be secure, I need to integrate the QR code scanner into the app rather than relying on an external app plus the Android Intent system to securely transmit data. I'm working on it.

Also, can you give me examples of existing Bitcoin apps/web pages that export private keys via QR? Which format(s) do they use?

Awesome!

I was thinking about this as I was just printing my old private keys to a paper wallet for safe storage.

Also, casascius uses qr-codes of private keys on his "bank"-notes: https://bitcointalk.org/index.php?topic=120896.msg1302079#msg1302079

Blockchain.info creates qr-codes with the paper backup function.

[teste]

Just today I uploaded a Blackberry test version:

http://code.google.com/p/bitcoin-wallet/downloads/list

Let me know if its installable on a Playbook and how it performs.

I downloaded the .bar version and tried to open the file. This message (translated to english) appear: "not possible to find the application standard"

I always install applications using the blackberry app world, but I didn't see Bitcoin Wallet Android on it.

[teste]

Goonie,

I see that to run a .bar file, it's necessary install programs on Windows/mac, http://blackberryempire.com/how-to-sideload-android-apps-on-playbook-2.0-using-ddpb/

I think to bitcoin Wallet Android be included on blackberry app world, it's necessary first be approved.
I'll wait this, because I don't have windows/mac machine and I'm a newbie user.
Hope you understand.

Really thanks.

[slothbag]

I've been using this Bitcoin Wallet for a month now and at first it was working well.  I upgraded it to the latest update a week or so ago and since then it would not connect to any peers.

After doing some network traffic inspection it appears the app is using 3 of the 4 DNS seeds listed on the wiki:

dnsseed.bluematt.me
seed.bitcoin.sipa.be
dnsseed.bitcoin.dashjr.org

But not bitseed.xf2.org

When I use the DNS server that my ISP assigns me, none of the three domain names resolve to any IP addresses.  But if I change my DNS server to say Google then they all respond ok and the app can connect.

This looks to me like my ISP is deliberately blocking these requests..  also it was quite effective at preventing me from connecting to the bitcoin network.

[Andreas Schildbach]

After doing some network traffic inspection it appears the app is using 3 of the 4 DNS seeds listed on the wiki:

dnsseed.bluematt.me
seed.bitcoin.sipa.be
dnsseed.bitcoin.dashjr.org

But not bitseed.xf2.org

Bitcoin Wallet uses bitcoinj 0.6 which includes bitseed.xf2.org in the list of hosts to query. Is your issue reproducable? Can you look up in the log for "DNS lookup for xxx failed." messages?

[Mike Hearn]

That's odd. I suspect there's no deliberate blocking but rather a configuration error on the ISPs end. Specifically I suspect they're trying to filter out IPv6 responses and breaking things in the process.

If you could contact your ISP and try and get them to look at the problem, that'd be great.

We need to make bitcoinj use hard-coded seed nodes and addr broadcasts. It's a known issue that it's too reliant on DNS seeding to get started.

[Andreas Schildbach]

We need to make bitcoinj use hard-coded seed nodes and addr broadcasts. It's a known issue that it's too reliant on DNS seeding to get started.

For several months I have sitting on a private branch a modification that persists node addresses across restarts. However, I never switched it live because the current bitcoinj API restricts too much how the querying works.

[Mike Hearn]

There are some other changes I think we need first. The heavy reliance on DNS seeding covers up some deficiencies elsewhere. They're easy to resolve.

[teste]

Goonie,

Will you send Bitcoin Wallet to BlackBerry App World?

What is the status?