Bitcoin Forum

Hello community,

i setup Whonix VM on Virtualbox where Electrum is pre-installed. I create standard wallet(with 2fa as i know is not free) and also saved seed on paper. I purchased some BTC from Mycelium app and transfered on Electrum. Transaction was completed. I checked Electrum wallet and there are my amounts.

Now i wanna to have watch-only Electrum wallet on mobile to check my balance and also to be able to get new address for transferring there another purchase. I am not always on Laptop. That Whonix is tor oriented and isolated OS where privacy is transferred under Tor and because of that i choose that platform. i do not like ms Windows.

I to setup that? to have watch-only wallet on my android for security. Or is there any other way to use Electrum on mobile with safe ?

How you have that managed?

As i now Electrum does not have fingerprint access with password.

I'm not sure where the option is (it's in one of the drop down menus) but I think you can get all 3 of your master public keys (they'll begin xpub, ypub of zpub when you find them). These can then be used to make a multisig watch only wallet on your mobile configured as a 2 of 3 (I think you have to configure it as multisig and not watch only though on the android device).

You can not setup a watch-only with 2FA wallet on Electrum, you can only use 'standard wallet'.

Read the link NeuroticFish post below to be able to setup 2FA watch-only wallet.

If you want to be able to setup a watch-only wallet, not that different on computers if compared with mobile phones too. Use this guide:

https://electrum.readthedocs.io/en/latest/coldstorage.html

If you still feel confused, then use this guide for mobile watch-only setup:

https://bitcointalk.org/index.php?topic=5237614.msg54149363#msg54149363 (the post by nc50lc).

Remember, you can not spend using watch-only wallet, you can only use it to generate addresses, make unsigned transaction and for broadcasting transaction that has been signed on cold storage wallet. Watch-only wallet does not have private key as you did not import any seed phrase or private, it can not be used fir making transaction.

That is not possible, standard wallet is standard wallet, while 2FA wallet is 2FA wallet on Electrum, they are not the same setup but totally different.

I just wanna want to have watch-only to see balance and send there BTC/ to get new address. i am not going to spend.

My wallet is standard wallet.
thanks for link.

I am not that sure it's not possible, I've founds this tutorial on how to do it:
https://bitcoinelectrum.com/creating-a-watch-only-version-of-your-2fa-wallet/

However, if this doesn't work or it's too difficult, and if OP wants to drop the "also to be able to get new address" functionality, he can always make a watch only wallet based on the one address he knows (or a list of addresses).


Edit: I see OP has standard wallet, then getting the master public key is easy. The rest of the answer still stands.

Are you sure about this?
In the OP, you said that you have created a wallet with 2FA. As mentioned by Charles-Tim, your wallet can't be both standard and 2FA.

If your wallet is 2FA, you have three master public keys.
If your wallet is standard, you have one master public key.


That guide works.
A 2FA wallet in electrum is actually a 2 of 3 multi-signature wallet.

In the 2FA wallet, you can go to "Wallet information" and get all three master public keys.
If you create a multi-signature wallet with those three master public keys, you will have a multi-signature watch-only wallet with the same addresses as the 2FA wallet.

Thanks for guides. My wallet is really
i created standard coz as i got transactions there needs a fees. so if i want use watch-only wallet on mobile need 2fa wallet?

No, you don't need to use 2FA. The instructions I posted above were to create a watch only wallet from a 2FA wallet, because from your original post it appeared you had created a 2FA wallet. It seems to have been lost in translation.

To create a watch only wallet on mobile from a standard desktop wallet:

• Open your wallet on your VM
• Click Wallet -> Information
• Open Electrum on your phone
• Create a new wallet and select "Standard wallet"
• Select "Use a master key"
• On desktop, click the QR code symbol next to your Master Public Key
• On mobile, scan this QR code and hit next

Ok i did as u guide me. Now i have watch-only wallet on phone?

now all private keys is saved on my VM?

You should do. If you open the wallet on your phone, and then tap on the wallet name in the top left, it should say "This wallet is watching-only" underneath your master public key.

I would also open the address tab in your mobile wallet (three dots at the top right -> Addresses) and the address tab in your desktop wallet (View -> Show Addresses if it isn't there), and double check the addresses match.

thanks for your guides. hardware wallet is expansive Ledger and trezors.

what about to use any linux distro on Virtualbox as cold wallet? u can turn there off internet forever. Is that good?

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I checked and it watch-only now. I can now just get address to send BTC for save and can't spend from watch-only wallet right?

Thanks for guide you and all of you.

VirtualBox-like solutions are considered not safe enough for cold storage, since malware on the underlying OS can record every move.
But if you're knowledgeable enough for VBox, you can easily use an USB stick with Live Linux as cold storage, as long as you always remember to unplug your network cable before booting from the stick. Even more, Tails OS provides a pretty good solution for this.

Right.
You can use your watch-only wallet for generating new addresses and checking your balance and transactions.
You can't sign transactions using your watch-only wallet and you will need your wallet on VM whenever you want to make a transaction.

Nice idea about Live USB and about Tails. Will think about it. One 8GB USB is enough. Thanks.

Also, if you plan on only spending from a single Electrum address (i.e. all Change addresses have been frozen via the GUI), you can repeat the import procedure above but pasting a Bitoin address instead of a master public key. It is more hassle-free than the mpk, at the expense of some privacy *potentially* lost by reusing an address.