Bitcoin Forum

I have an Electrum wallet on my laptop. I just installed an wallet App on my cell phone. What I need to know is How can I transfer funds from
the electrum wallet located on my laptop to the electrum wallet App located on my cell phone??? I can not possibly "copy/paste". I have
heard someone mention Qr . I have seen the QR symbol on both wallets, but I have NEVER used this feature (if that is what you are going to suggest).
Please explain in layman terms please... I hope to hear from someone fast!!!

Your coins are not stored in your laptop. They are stored in blockchain. So, you don't need to transfer your coins from your laptop to your mobile.
You only need to create a new wallet in your mobile and import your seed phrase into the application.

If you don't know your seed phrase, click on "wallet" at top of the window and then click on "seed".

Electeum wallet on laptop with electrum wallet on phone has the same derivation path, so you have no problem. Just do as hosseinimr93 has adviced. We believe you remember what passed phrase is? The 12 to 24 words the wallet generated for you when you first opened the wallet on laptop. Input the words (seed phase) in the space provided on your phone while you open the wallet.

https://i.imgur.com/K0TTqse.png

If you are going to transfer your funds by using QR code you can use the QR code scanner from your Electrum on the laptop then open your wallet from mobile Electrum and go to receive it will show you the address and the QR code scan it using your laptop on the front of the camera.

It shows something like this image below.

https://fastandclean.org/wp-content/uploads/2019/04/Screenshot_20190411-1642342_LI.jpg

Then use this from your laptop

https://i.imgur.com/Mbvm4Ao.png

Now you can set the amount you want to transfer after successfully scan the QR code from Laptop to mobile.

Transferring the bitcoin through bitcoin blockchain network will not be the good option, although, it can be an alternative. But like the OP asked, he wanted to transfer the bitcoin from laptop electrum wallet to phone electrum wallet, which means he wants to move the whole funds. And, if he send all by transferring all the coins through bitcoin blockchain  network to another electrum(phone) wallet, transfer fee will be charged. Instead, using the seed phrase will be better.

Although, I know you know this, but just for the sake of the OP to understand.

Since the coins are stored on the blockchain tagged to each private key there is no such thing as "Copy paste" here. Each wallet has a different private key underlying it and thus if you need to transfer them from one to another, just make a transaction from the desktop one to the App one.

It will cost some fees for sending the transaction but it will suffice for now.

You can request the wallet App on your phone to give you a receiving address. Then enter that address as sending address on dekstop wallet and send the coins.

Using QR codes between phone and PC is a hassle IMO.

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Electrum has some "Sweep" options as well IIRC?

There is no "sweep" function on the mobile app.

OP has to decide whether they want the wallet to be mirrored across both devices which can be achieved by simply restoring from the desktop seed phrase to the mobile app, or whether they want to some of the coins from the desktop wallet to the mobile wallet, which they can do by making a standard transaction. Mirroring the wallets obviously means you can access your coins on either device, but greatly decreases the security by having the same wallet being susceptible to multiple vectors of attack.

I always think its better to only carry around a small amount of "day to day" spending bitcoin on a mobile wallet, and keep larger amounts in a more secure wallet.

there's a share icon on the request screen on electrum android. it looks like 3 points with paths between them. you can simply use that to email yourself the address. then just pay to that using your PC.

How would it be different from importing the same seed to both devices? Security-wise, it would be identical since either methods would allow an attacker to take control of the funds the same way.

If anything, I feel 1-of-2 multisig would just make the transaction bigger than necessary and wouldn't provide much benefits.

No, a 1-of-2 MultiSig is relatively pointless...

It introduces unnecessary complexity and increases transaction size... additionally, it can make recovering funds into different wallet apps very difficult/impossible.

Either use the same seed on both devices... and have the wallet "mirrored" or "cloned" (or whatever you want to call it.) and both devices will have identical addresses/transactions/balances and you can spend your funds from either.

OR

create 2 completely separate wallets on the 2 devices and operate them as independent wallets... in which case, if you want to get funds to the Electrum app on your phone, you would need to create and broadcast a transaction from the desktop wallet on the laptop (and pay the transaction fee etc).

MultiSig is a P2SH... it's not just a simple "attach a signature" like a "normal" transaction, so while it's true that only one sig is needed to spend for a 1-of-2... you still need to include the full redeemscript, which will need to be provable for BOTH sigs, so will require you to provide TWO pubkeys...

Have a play with the calculator here: https://jlopp.github.io/bitcoin-transaction-size-calculator/

Noting that for a P2PKH transaction, #sig=1, #pubkeys=1, but for a 1-of-2 P2SH, #sig=1 and #pubkeys=2... if we are creating a single P2PKH output, it'll gives transaction sizes of 192 bytes v 231 bytes respectively.

This gives a good breakdown of it: https://bitcoinops.org/en/tools/calc-size/

You can see how in P2PKH: 1 sig + 1 pubkey, whereas in the 2-of-3 you need 2 sig + 3 pubkey... likewise with 1-of-2, you need to have 1 sig + 2 pubkey