Bitcoin Paper Wallet For Android
I’ve already written up a Tutorial on the best way to Make A Paper Wallet. However, in my Tutorial on how to use an old Android mobile phone to create a DIY Bitcoin Hardware Wallet I mentioned using an Android app to create Bitcoin paper wallets. This software could be used to create Bitcoin paper wallets and store them on your phone. In this Review I will show you the software and options. I will also write a Tutorial to explain its use in more detail. For now, let’s look at the Android app Bitcoin Paper Wallet.
Note: I know iOS is coming close to being half of my mobile traffic, so I’m going to ask all you Apple fans to help me out here. Because this app is Android only, could someone recommend an iOS equivalent here? Sign up to my blog or use your WordPress login and comment on this post with your favorite iOS equivalent to this app! Maybe I’ll invite a user to write a guest review to be posted on my site.
Bitcoin Paper Wallet is an open source Android app that allows you to securely create Bitcoin address and private key pairs. It allows you to generate them in several formats. You can also use this app to pull up QR codes to Bitcoin addresses or manually input Bitcoin addresses and pull up a QR code. There aren’t a lot of options to discuss, but what the app itself does is powerful. Let’s get started.
If you remember from my discussion of Bitcoin Addresses and Private Keys, a paper wallet basically only needs two parts. The top line in the app is a Bitcoin Address. If you click on the bar code button next to that line you’ll see a barcode with the Bitcoin Address information embedded in it. It also has three links: one that can be used with Bitcoin applications and two to view the address you’ve created on online block explorers. There is also a print button, if you want to print a giant barcode with a tiny address on it.
Although I don’t think this is a good placement for this button, there is a button right under the address the app just generated that says Generate Another. Clicking on this button causes the app to generate a new address. Be careful clicking this button. If you’ve already sent Bitcoin to the address you previously generated and didn’t write down the Private Key further down in the app you can’t pull up previous addresses and keys. They’re now lost to the wind. Once you’ve written down all the information you need, feel free to click this button and it will wipe all memory of an address you’re ready to use.
The app then explains that the next line is a Private Key. This Private key is in Wallet Import Format. This means that anyone that has that line can control any Bitcoin sent to the associated Bitcoin Address. Keep this information absolutely secret.
There is another barcode button here as well. Clicking on it brings up a barcode with the Private Key information embedded in it. If anyone were to scan this barcode they would be able to move any Bitcoin you’ve sent to the Bitcoin Address associated with it. If I haven’t said it enough, keep this information absolutely secret. Again, there is a Print button, but I don’t see why you’d use it. The same with the Share button here. I don’t recommend either one. But they’re there if you want them for something.
Another thing to note is that, in the options of the app, located by clicking the Gear icon in the upper right corner, you can select which format you want the app to create Private Keys. There are three options: Wallet Import Format, Mini, and Old WIF. Wallet Import Format is pretty standard, so I stick with that. Mini, I’m assuming, is just a compressed version of that. I really don’t know what Old WIF is. It sounds like a horrible whiskey of some kind. I recommend just sticking with Wallet Import Format. There is also an option here to add an extra fee. Again, this isn’t a feature I use when I’m creating paper wallets. Just know that it is there.
The next line in the app gives you the option of entering a password and encrypting the private key. If you’re going to be storing the paper wallet information you generate with Bitcoin Paper Wallet I highly encourage you to use this feature. It’s an added layer of security you should not ignore. Simply enter a password and click the Encrypt Private Key button. The app will go through the encryption process and the Private Key type will change to BIP 38 (password protected) format. Clicking on the barcode again now shows the ability to select and switch between WIF (Wallet Import Format) or Encrypted barcodes.
Another neat feature of this app is the ability to recreate addresses and barcodes, as well as decrypt previously encrypted keys. Let’s say you use this app to create a list of paper wallets, both Bitcoin Addresses and Private keys, that you’ve stored in a spreadsheet. If you were to copy an encrypted Private Key from the spreadsheet you could paste it into the Private Key section of the app it would say “Not decrypted yet” in the address section. If you then put your password into the Password line and click Decrypt Private Key it would then show you the address and barcodes. You could then recall old information and, if you were so inclined, sweep the address to move funds into the Bitcoin wallet of your choice.
This feature does bring up a possibility that I’m going to warn against. Because you can enter a private key manually and recreate a Bitcoin address it is possible to enter what is known as a Brain Wallet here. I cannot stress this enough: do not do this. Brain wallets are notoriously bad, even password protected ones, and theft from them has crushed a lot of Bitcoin users. As humans we are very poor and very predictable computers. Please leave random generation to the machines.
As I said above the security of this app is impressive. The app prohibits screenshots which means that, not only are you refused the ability to do so, possible malware on your phone cannot use the screenshot feature either. The app also does not write to disk in any way, so nobody can scrape your phone storage to find raw information from the app. In addition to that, the app works completely offline, which is why I recommend it for my DIY Bitcoin Hardware Wallet project.
There is a section of the app for entering raw transaction information here. I’ve only done this to see what data was in a transaction when I was helping a user track down some funds. This app gives you the option of using this data to retrieve unspent outputs. I’m not going to discuss this feature or endorse it at this point. I honestly don’t know enough about the process to say anything meaningful about it. If I ever get the chance to use it I will update this review or add it to the Tutorial I’m going to write. Until then, just know it’s there.
There is only one feature I would like to see with this app, but I never took the opportunity to write the developer. The print feature of the wallets is super basic. I would like to see it print pretty wallets like the ones you get from running BitAddress.org’s software. Even if they weren’t quite as pretty it’d be a vast improvement over giant barcodes on a piece of paper. And, although it would possibly compromise the security I mentioned above, I’d like to be able to save images of those pretty paper wallets. If a happy medium could be found here, I’d be happy. Other than that, I think this app is darn near perfect.
I love this app in nearly every way. The interface is clean, with only the “Generate Another” button being an issue. The functionality is incredible for such a light piece of software and and it’s also very intuitive. The security is tight. It can be used in an offline setting like my DIY Bitcoin Hardware Wallet project or on the fly for quick uses like my everyday mobile phone. I can’t give this app higher marks. If you’re looking for a way to make Bitcoin paper wallets on the go, I highly recommend Bitcoin Paper Wallet.