Bitcoin Wallet for Android

[Mike Hearn]

It was wrong before, and after the reset it became correct.

Why can they be different? It can happen for a couple of reasons, one is bugs (which obviously need to be fixed) and the other reason is if you lose synchronization to the network for some reason. For instance if you have two coins and then send one of them to someone else but the transaction never "goes through", your wallet will have your balance be 1 coin. But if you then reset your wallet then you'll get back in sync with what the rest of the people using Bitcoin perceive, which is that you have 2 coins.

Transactions can fail to go through for a number of reasons, one obvious one is that the fees are wrong. Earlier versions of the app didn't always calculate the min required fee correctly, so you could create spends that some nodes would accept and others wouldn't. Worse, they let people change the fee themselves, so it was possible for the app to do the right thing and then users broke it by setting the fee to zero.

These issues are getting fixed over time. The latest version does fees correctly, for instance. But it seems we may still have a bug that lets peoples wallets get desynced from the network sometimes. I've never had this happen to me and I use the app quite a lot, but there can be bugs related to timing or different devices.

[1713303027]

1713303027

[goose20]

It was wrong before, and after the reset it became correct.

Why can they be different? It can happen for a couple of reasons, one is bugs (which obviously need to be fixed) and the other reason is if you lose synchronization to the network for some reason. For instance if you have two coins and then send one of them to someone else but the transaction never "goes through", your wallet will have your balance be 1 coin. But if you then reset your wallet then you'll get back in sync with what the rest of the people using Bitcoin perceive, which is that you have 2 coins.

Transactions can fail to go through for a number of reasons, one obvious one is that the fees are wrong. Earlier versions of the app didn't always calculate the min required fee correctly, so you could create spends that some nodes would accept and others wouldn't. Worse, they let people change the fee themselves, so it was possible for the app to do the right thing and then users broke it by setting the fee to zero.

These issues are getting fixed over time. The latest version does fees correctly, for instance. But it seems we may still have a bug that lets peoples wallets get desynced from the network sometimes. I've never had this happen to me and I use the app quite a lot, but there can be bugs related to timing or different devices.

I'm happy with that explanation.

And I thank you for taking the time to provide such a response.

Cheers

[bernard75]

Worse, they let people change the fee themselves, so it was possible for the app to do the right thing and then users broke it by setting the fee to zero.

But it will be still possible to change them manually?

[Andreas Schildbach]

Worse, they let people change the fee themselves, so it was possible for the app to do the right thing and then users broke it by setting the fee to zero.

But it will be still possible to change them manually?

What usually happens if people set them to zero is that people are waiting for days to get their transactions confirmed, which means they will mail me for support. To improve the situation, fees are now adjusted to the exact minimum needed. Manual adjustment is no longer possible. In future, I might allow adjusting upwards, but not downwards.

[Syke]

To improve the situation, fees are now adjusted to the exact minimum needed.

Define "minimum needed." I send a lot of transactions with 0-fee, and because I have old coins 0-fee is the minimum needed.

[BurtW]

Any comment on this story with respect to my Android wallet?

http://www.bbc.co.uk/news/technology-23179522

[Mike Hearn]

The exploit is easy to reliably detect (it can't be obfuscated) so as long as you stick to just using apps from the Play Store you'll be fine. Once security updates are issued, you can go back to installing random apps from anywhere again.

[TObject]

Hello,

I installed Android wallet by Andreas Schildbach on a phone that does not have an SD card. Can you help me figuring out how to get the keys backup file out of the phone?

The “Export private keys” routine says it saves the backup to “/storage/emulated/0/Download/” location.
However when I browse the phone over MTP, I see no such folder. I do not have “data/data/” ether.

So, how do I get to the backup location?

Android version 4.2.2

Thanks.

[Andreas Schildbach]

MTP already shares the "SD-card", so look for a "Download" directory.

Its probably easier to backup to your email account or Google drive. After exporting, you're getting asked to Archive and select an app for that purpose.

[TObject]

The Download directory is there, but it got nothing except a few pdf files I downloaded through Android web browser.

I will try your other suggestion. Thank you.

Edit: Hmmm, I still need access to that folder in case I need to restore the backup, as restore does not seem to support email or Google drive, only internal/external storage.

[TObject]

Ok, I figured it out. The issue is described here:
http://commonsware.com/blog/2011/08/31/mtp-external-storage.html

The workaround is as follows. Go to Settings – Apps – All, Media Storage, Click on “Clear cache,” then reboot the phone.
After that the bitcoin-wallet-keys backup file will show up in the “[\Internal storage]\Download” folder, via MTP.

[Dabs]

Hey, I updated and I can't set the fee anymore? Oh, it was done on purpose. Okay. Yes, there should be an option to be able to adjust it upward, even if only by a satoshi.

[Andreas Schildbach]

What do you want to achieve by raising the fee by one Satoshi?

[2weiX]

requests:

- make "export to multibit" an option
AND/OR
- make "export to aes.json blockchain.info" an option
AND/OR
- make "export w/o password" an option

as well as provide a "sign clipboard contents with default address" an option.


here's why:
bought a couple of Avalon Chips from my Android wallet, now they're making me sign stuff with the address.
Means I need to jump through a bunch of hoops to be able to do that.

[Andreas Schildbach]

requests:
- make "export to multibit" an option
AND/OR
- make "export to aes.json blockchain.info" an option
AND/OR
- make "export w/o password" an option

As MultiBit and Bitcoin Wallet use the same interchangable export format, MultiBit is already supported.

I think someone mentioned Blockchain.info can read that format as well, so its also supported.

Exporting without password will not be supported for security reasons.

as well as provide a "sign clipboard contents with default address" an option.

Its not top prio, but at some point I'd like to support signing and verifying as well. Can you open an enhancement request at

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

[2weiX]

requests:
- make "export to multibit" an option
AND/OR
- make "export to aes.json blockchain.info" an option
AND/OR
- make "export w/o password" an option

As MultiBit and Bitcoin Wallet use the same interchangable export format, MultiBit is already supported.

urgh - just needed to rename it to ".key"
and enter the correct pwd ^^
maybe you can get the multibit guys to remove the forced naming convention when opening a file.

Exporting without password will not be supported for security reasons.

I can get behind that.

as well as provide a "sign clipboard contents with default address" an option.

Its not top prio, but at some point I'd like to support signing and verifying as well. Can you open an enhancement request at
http://code.google.com/p/bitcoin-wallet/issues/list

Uhm, yeah, sure.

^__^

[Dabs]

What do you want to achieve by raising the fee by one Satoshi?

It's still higher than the default minimum fee. When I said one Satoshi, that could also mean another 0.0001 or something similar, so now I'm paying double the default minimum fee.

Exporting without password will not be supported for security reasons.

I think it's been mentioned elsewhere in this thread, if you've got root, you can export the private key already. But people who root their phones probably know what they're doing. You might want to add an option that can only be set by root, for example, and then allow those people to set the fee as they like (zero or otherwise). This way, you still prevent newbies from doing this accidentally. A warning can also work ("warning: you are attempting to broadcast a transaction with a fee that is too low. Are you sure?")

Or something like that.

[Andreas Schildbach]

People who know what they're doing can compile Bitcoin Wallet from source. Feel free to do so, it's open!

If you're root on your phone you can copy the wallet and unencrypted key backups anyway. See the readme.

Back to the idea of raising the fee: What do you want to achieve? I'd like to understand the reasoning.

[Dabs]

People who know what they're doing can compile Bitcoin Wallet from source. Feel free to do so, it's open!

If you're root on your phone you can copy the wallet and unencrypted key backups anyway. See the readme.

Back to the idea of raising the fee: What do you want to achieve? I'd like to understand the reasoning.

Raising the fee by any amount gives the transaction a higher priority. Correct? Therefore, it should be confirmed faster than everything else that just gives the same standard fee or less. Even a 0.0001 increase should satisfy most miners and give them incentive to include your transaction in the next block.

[Mike Hearn]

But we are not even close to the 1mb size limit today so miners could also just accept your transaction without the higher fee.

Do you experience confirmation delays often?