You can use bip 38 to create an HD wallet  - just use the decrypted 64 char hex private key as entropy to create the 24 word passphrase

Using bitaddress.org (https://github.com/pointbiz/bitaddress.org):

Create a bip38 encrypted single private key using the 'Paper Wallet' tab and save it somewhere.
Copy the encrypted private key and open the 'wallet details' tab and paste;  enter the bip38 password to decrypt.
Scroll down and copy your Private Key Hexadecimal Format (64 characters [0-9A-F]).

Use https://github.com/bip32JP/bip32JP.github.io to create HD wallet:

Paste the Hex private key you just copied as the entropy.
select the 'Base 16' radio button and '24 words' below Bip39 passphrase.
Click 'Generate New Phrase' and a 24 word phrase should be generated.

Double check you can repeat the process with the same result before commiting any funds etc.

You can do cold storage with HD using an xPriv paper wallet, but unfortunately there's no BIP38 for that. There should be.

It's not the jingle, it's knowing when to play the jungle. Generally when you open your wallet, it only scans for some of the more recent addresses, and you have to trust us when we say we don't log them. In SPV wallets, they try to obfuscate which is your address by asking for different random ones along with yours, so the node doesn't know which is yours and which isn't. Also, it only scans it once when you open, or if you tell it to manually refresh (or if something in the wallet changes). Basically, the less often you ask, and the fewer addresses you ask for (or your own), the better. Doing a notification would basically require you to keep pinging nodes every few minutes for all or most of your addresses (since there's no way to know if just the most recent one, or an old one you gave out a while ago, is the one that will receive), and even if you obfuscate with lots of fake addresses, eventually yours will be fairly easy to pick out from the group.

FYI, chainalysis claims bloom filter obfuscation sucks, and they can get around it very easily.


If you select your account, there's an option to "Export" the account in xPub format. That's the same as sharing a public address. Anyone with an xPub key can import it as watch-only and see all your addresses and balances, but can't spend from it.

Hm, so could you now or in the future...
import your Mycelium xPub to Electrum, then use Mycelium to sign unsigned TXs generated by Electrum?
OR
import your Mycelium xPriv to Electrum, delete the xPriv out of Mycelium, leaving only the xPub, then use Electrum to sign unsigned TXs generated by Mycelium?

You can already do something very similar, not with xpriv but with entire seeds.
Just generate a BIP39 word list and put that into a qr code (hint: mycelium entropy can do this).
Create one or more passwords however you prefer to.
Scan the seed words QR code, enter optional password, select account, spend.
That way, you have a HD wallet on paper, password required, each password gives another wallet.

Select your transaction in the transaction list, and Show Details. You can verify the Miner Fee at the bottom to check if it's still the same.

I see you answered most questions yourself already

The "wrong" numbering is a difficult topic.
While it might appeal to some if the account name matched the derivation path index, I guess most users are neither aware of this derivation nor used to 0 based numbering.
I am actually not sure how others do it, isn't your first account named Account 1 on myTrezor as well?
And speaking of "first account", "second account" it is likely easier for most to connect those to "1" and "2" than starting at "0"...

Maybe we should settle for a compromise, starting at 0.5?
(Or ask authority - https://xkcd.com/163/)

I asked for it, but I don't remember getting any reply.