For the rejoice of Monero users everywhere, since version 1.6.1 Monerujo features integration with the Ledger Nano S. This guide should help you set it up and use it. This enables you to tie together the convenience of Monerujo with the security of a hardware wallet, for a best-of-both-worlds super duper private crypto combo.
Setting up your wallet for the first time
Ok basics first: you’ll need an android phone with Monerujo installed, a Ledger Nano S with the Monero app installed, and an OTG cable to connect both.
You may need to enable OTG on your phone (I needed in mine) for it to work. Go to your phone settings and make sure OTG is enabled. If you can’t find it try searching on the help menu. Turn it on.
Plug in your Ledger. It should light up and ask for your pin. Enter it. Your phone should ask you if you want to open Monerujo. Say yes, of course.
Open the Monero app on the Ledger. It may want to open Monerujo again, that’s fine.
In Monerujo, click on the + circle button to create a new wallet. Since you have plugged in the Ledger, it should have only one option: Restore from Ledger Nano S. Do it.
Choose a name for your wallet, and a password for its use in Monerujo. You can choose to enable fingerprint access there, which is pretty convenient. In both cases, Monerujo will encrypt your wallet files on your phone using a crazy secure password, which you can learn more about here.
You must also enter a height or date to restore the wallet from. This is to avoid syncing from the beginning of times, and it’s mandatory. Enter a date you’re sure it’s before you started using the wallet and that’s all. You can use YYYY-MM-DD or YYYYMMDD it’s the same.
Monerujo will ask you to confirm on Ledger device. Your Ledger will ask something like Export View Key? Do it. It should start retrieving subaddresses. This is normal, let it do its thing.
Monerujo will then show you information about your wallet on Monerujo’s side. Write that down. You’ll notice there’s no wallet seed there. That’s normal because your wallet seed is stored inside the Ledger and never sent anywhere, that’s what makes it safe. That Restore Password you see there is what you should use in the future to restore a backup of the same wallet files in Monerujo. This is in case you want to keep your notes and names, for example. It’s not critical, so if it makes your brain hurt, leave it.
Well done! You should have your wallet ready to use.
Using your wallet afterwards
The first time you open it, Monerujo will need to scan for subaddresses again (for technical reasons), and then scan Monero’s blockchain looking for XMR that belongs to you from past transactions. That’s what it’s doing when it says scanning and the number of remaining blocks.
How long it takes will depend on the restore height from step 5. Be patient, the first time is the worst, afterwards, it will pick up from where you left it.
Close it, and it will save this state and be ready for quick, future usage.
You don’t need to sync or see your whole transaction history just to receive some moneroj. You do need to have your Ledger plugged in though, as Monerujo will use that to be sure your files weren’t tempered with and you’re seeing the real address and not a fake, hacker-tampered, one. Just click on the three little dots next to your wallet’s name on the main screen, and pick Receive.
You’ll see a Public Address there, and you can generate a different one if desired. Just copy it and share it. You can also show the QR code if you’re next to the sender.
For this you’ll need your Ledger. Connect it to the phone, unlock it with your pin, and open the Monero app.
Once in Monerujo, open your wallet. It will either ask for your password or fingerprint, whatever you set up when creating it. You’ll have to confirm on the Ledger. Once you do, the wallet will open, it will sync, and once finished, will enable the Give button.
If you click it it will ask for your wallet password, just to be safe it’s you and not somebody gently using your finger while you sleep, for example. It will take you to the send screen. Write or paste the receiving address, then the desired amount, then confirm.
Now your Ledger will ask you to accept both the fees and the transaction. You do that by scrolling with the right button until the very bottom. You’ll see the Accept dialog, and by clicking both buttons at the same time, you do.
Monerujo will ask for your password again, just to be really really sure it’s you, then it’ll send your sweet moneroj.
Sweet extra stuff
Monerujo’s accounts and subaddresses are available for Ledger wallets as well. This takes receiving and classification of funds to a whole new level, and it’s described and explained in detail in this article.
I hope you enjoy using your Ledger with Monerujo. Please let me know if you encounter any error in this walkthrough. Please remember that Monerujo’s code is completely open source and its development is entirely sustained by donations, so if you find it useful and makes your life better, please send some love in the form of XMR to the Monerujo Team. It’s both heartwarming and a great way of practicing with your Ledger ;)