Mycelium Bitcoin Wallet

[RGBKey]

A small thing but... an audible notification when bitcoins are being received be nice feature.

This would be nice too, there isn't any kind of notification at all.

[westkybitcoins]

A small thing but... an audible notification when bitcoins are being received be nice feature.

This would be nice too, there isn't any kind of notification at all.

I suspect this might be harder than many think.

If so, it might make a great pay feature of the product.

[RGBKey]

A small thing but... an audible notification when bitcoins are being received be nice feature.

This would be nice too, there isn't any kind of notification at all.

I suspect this might be harder than many think.

If so, it might make a great pay feature of the product.

I never said it would be easy, but there are things I would like to see in this wallet before this.

[Rassah]

A small thing but... an audible notification when bitcoins are being received be nice feature.

With a possibility to switch it on/off of course :-).

Good idea. I'll add it to the team's to do list!  (Personally, I love the satisfying coin jingling sound of the other wallet every time I get money )

[(A)social]

A small thing but... an audible notification when bitcoins are being received be nice feature.

With a possibility to switch it on/off of course :-).

Good idea. I'll add it to the team's to do list!  (Personally, I love the satisfying coin jingling sound of the other wallet every time I get money )

Public domain 
http://www.mediacollege.com/downloads/sound-effects/money/
http://www.mp3olimp.net/cash-register/


P.S. I'm glad that you joined the Mycelium team, Rassah, I like what you write in your posts in the various threads (especially those regarding freedom). 

[MarcoPon]

(Personally, I love the satisfying coin jingling sound of the other wallet every time I get money )

Exactly!  Thanks!

[Rassah]

Hi everybody! I'm going to start doing weekly posts, showcasing one Mycelium feature I find interesting, and updating on what's going on with our team and development. We have tons of awesome stuff being worked on!

So, without further ado, this is the feature that first got me into Mycelium (and impressed the heck out of me at the San Jose conference):
Spending from cold/paper wallet

1. Take out printout of private key
2. In Mycelium, go to the Menu is the top right corner (three vertical dots)
3. Select Cold Storage
4. Press QR Code, and scan the private key of your paper wallet.

This loads the private key into your phone's secure memory, but does not save it to your storage.

5. Proceed to spend as normal, entering the Bitcoin address from either the QR code or clipboard, and entering the amount. Note - Mycelium will retrieve the balance of your paper wallet and will show that once you click the Enter Amount keyboard button (I asked the guys if they could make the balance a bit more prominent).
6. Hit send, and Mycelium Wallet will broadcast your transaction, send all the remaining change back to the paper wallet, and wipe the private key from your phone's memory.

This is a pretty great way to spend money from secure cold storage, without relying on a separate computer (as in Armory/Electrum) or a hardware wallet device (Trezzor). It's not as secure as offline signing, but it's much better than a wallet kept on your computer. When Jan first demoed this for me, he whipped out a private key on a folded business card stored in his pocket, spent money from it, and stuck it back into his pocket, with his phone posing no risk to his bitcoins.


In the news, the Mycelium team is traveling to the Inside Bitcoins conference in Berlin (but I won't be). While there, they will be unveiling a rather exciting and important new service that will be built right into the Mycelium Wallet. I regret not being able to go, because this new thing of theirs is really awesome, is related to a bunch of recent news, is very important for bitcoin's ecosystem and may help speed up adoption immensely, and I would have been promoting the hell out of it even if I wasn't a part of the team. So if you are going to the conference, make sure to find the Mycelium guys and pester them with questions! (I won't be paid unless you pin them against a wall and ask them all about it )
And if you can't make it to the conference (It's €445!!!), don't fret. I'll still fill you in on the whole thing right here. I can't wait!

[bigbeninlondon]

I noticed some discussion about message signing in the beginning of this thread; any progress on that?  It's the only way to prove you own your address without spending from it.  I'd rather not have to import the private key to another client just to sign the message, but have required on at least two different occasions to prove my ownership of my Mycelium address and couldn't, so had to use one on my client and wait until I returned home to conduct my transaction.  Very inconvenient.

[RGBKey]

I noticed some discussion about message signing in the beginning of this thread; any progress on that?  It's the only way to prove you own your address without spending from it.  I'd rather not have to import the private key to another client just to sign the message, but have required on at least two different occasions to prove my ownership of my Mycelium address and couldn't, so had to use one on my client and wait until I returned home to conduct my transaction.  Very inconvenient.

This, I had to send coins from a blockchain.info address because I couldn't sign messages from my phone. Pretty annoying.

[Jan]

Thanks for letting us know what you think is missing out. We will increase message signing priority.
The thing is that we are all using Bitcoin for different things. I have actually only had to sign a message once, so I kinda thought that this was the norm.
Please continue to tell us what you think is the most important focus area.

[RGBKey]

Thanks for letting us know what you think is missing out. We will increase message signing priority.
The thing is that we are all using Bitcoin for different things. I have actually only had to sign a message once, so I kinda thought that this was the norm.
Please continue to tell us what you think is the most important focus area.

Thanks for being great devs <3

[TheButterZone]

One use case for message signing http://wiki.bitcoin-otc.com/wiki/Bitcoin_address_authentication

[RGBKey]

Another case for message signing: https://bitcointalk.org/index.php?topic=437004.0

[apetersson]

I implemented message signing for mycelium. It is very very likely that it is part of the next feature release.
We also use signing for other stuff internally

[Vandroiy]

I just saw a Mycelium wallet misbehave heavily: a transaction was shown as sending only the fee, not the rest. However, on the block chain, it was sent. Mycelium balance was then out of sync with the block chain.

Didn't happen on my device, so I don't have more details right now. But naturally I'm suspecting mutated transactions to be involved.

[Rassah]

I just saw a Mycelium wallet misbehave heavily: a transaction was shown as sending only the fee, not the rest. However, on the block chain, it was sent. Mycelium balance was then out of sync with the block chain.

Didn't happen on my device, so I don't have more details right now. But naturally I'm suspecting mutated transactions to be involved.

Erm, somewhat bad timing with this whole bitcoin-wide attack thing. The guys may be on their way to Berlin as we speak, so probably won't get a chance to look at things till later. I asked them for feedback on whether Mycelium is affected by this thing. Will let you know soon as I hear back.

[Jan]

I just saw a Mycelium wallet misbehave heavily: a transaction was shown as sending only the fee, not the rest. However, on the block chain, it was sent. Mycelium balance was then out of sync with the block chain.

Didn't happen on my device, so I don't have more details right now. But naturally I'm suspecting mutated transactions to be involved.

When you see sending/receiving in the main balance view Mycelium reports how your balance is currently affected positive/negative. If you are sending to your self your balance will be affected negatively by the amount you send and positively by the amount you receive. The remainder is the fee. If you only see the fee I guess that you are sending coins to yourself. If you want to know for sure what is happening you can go into the tx history, click a transaction, and "Show Details". There you will see which addresses send and receives coins.

[Jan]

I just saw a Mycelium wallet misbehave heavily: a transaction was shown as sending only the fee, not the rest. However, on the block chain, it was sent. Mycelium balance was then out of sync with the block chain.

Didn't happen on my device, so I don't have more details right now. But naturally I'm suspecting mutated transactions to be involved.

Erm, somewhat bad timing with this whole bitcoin-wide attack thing. The guys may be on their way to Berlin as we speak, so probably won't get a chance to look at things till later. I asked them for feedback on whether Mycelium is affected by this thing. Will let you know soon as I hear back.

While the malleability 'attack' is raging all wallets (including bitcoin-qt) are affected, but in a minimal way.

This gets a bit technical: When you send a transaction you (most of the time) send change back to one of your own addresses. This is pretty normal and happens all the time. Because wallets may choose to spend this change (especially if the wallet is running low) a new transaction (created before your previous transaction confirmed), may reference outputs that are not valid because of the malleability attach. Gah... this is hard to explain in few words...

In other words: If you are sending transactions in rapid succession before your previous transactions confirm you risk that a second transaction gets invalid, as in "will never confirm". This will continue to be an issue until the malleability 'attack' subsides or the Bitcoin protocol disallows malleable transactions.

[RGBKey]

Quick question, does Mycelium periodically refresh the balance when the app is left open? If it's not, that would be a nice thing.

[Jan]

Quick question, does Mycelium periodically refresh the balance when the app is left open? If it's not, that would be a nice thing.

It isn't. The balance automatically refreshes when the main screens are opened (showing the tabs Keys, Balance, Tx history, Address book). But, automatic refresh would be nice, and even better real-time notifications... working,  working, working on improvements