Bitcoin Forum

I have made an Android app for scanning Bitcoin and other cryptocurrency address QR codes and showing their funds. I would love to receive some feedback on the app functionality and feature requests. You can download the app for free on the PlayStore https://play.google.com/store/apps/details?id=com.walletwatcher .

If you are wondering what the use case for this app is:
When I started with Bitcoin I held my BTC and other crypto on a paper wallet. Since you shouldn't store your paper wallet on your PC, I needed a way to easily scan the address and view the funds, without having to import the Private Key itself, since this would compromise the security of the wallet. So I developed an app to do just that. You can scan your address with your camera and instantly see the funds in BTC, USD and EUR.
I have bought a ledger now and with the app I don't have to connect the ledger to my PC to see the funds, which also saves a lot of time.
A second use case is for all the curious people out there. If you happen to see a crypto QR code somewhere outside and wonder much money there is on that address, you can quickly scan the QR code and find out.

This is something that is close to the solution I am looking for. I want a APP that scans the QR Code and then convert the

content to a Text file. Let's say you have tons of paper wallets and you quickly want to scan the Private keys of all the paper

wallets, while you are "offline" and then sweep the content to another address. This will come in handy when you have a lot

of paper wallets and you want to claim all these FREE forked coins. Most QR scanners are online... so this is a security threat.

I did a test using an old device (running on Android 5.0.1) and there seems to be an issue for fetching the data (it just shows "0" for amount). For BTCitcoin it stays at "0" but for other coins, it's stuck on reloading.
Update:
Solved.

---

A small suggestion:
- Make it in a way to automatically detect which coin it has saved, based on its address type (ATM, I have to choose it manually).

Could you tell me what address you were using? Does the btc donation address work?

To your suggestion: Can you 100% identify the coin through the address? I mean with all the new segwit etc. formats?

Looks like it has something to do with my network (tried it with a VPN and everything works now).

Somehow, I failed to see that part (face-palm).

---

• You might want to add a note on how to delete (swipe left) each address, within the app.
• Perhaps, the currency change (BTC/$/€) can be applied automatically (instead of updating each individually).

Sounds like a nice application. Since I use iOS, I will not download it immediately. But as soon as I download it I will give you information about the application.

An iOS version will come out soon. I am currently waiting for the new generation of MacBooks to be able to code for iOS, because apparently you need to own a Mac to develop for iOS devices.

Hmm.. that's strange. Do you know if some websites are banned in your network? Or did you change your location by using a VPN? I'm looking into setting up a server to prevent these problems, if it has to do something with region locking.

Yeah, the swiping seems to be more intuitive for iOS users. On Android users are used to tapping and holding the item, don't they?

And yeah, good point about the currency change. I am putting it on my ToDo-List. :)

PS: I would love to get more reviews / feedback on the PlayStore. You would really help me out writing an honest rating there, if you don't mind. :)

I like the features very cool app. I didnt download it but the google playstore page looks exciting. Goodluck with the app :)

Yes, some websites (pornographic) are blocked (due to my location & network) and I can't access crypto exchanges that are being operated within the US (restriction is from their side).

Exactly.

Done ;)

OK, so me hosting an extra server will most likely solve the issue. I'm looking into it. :)

Thank you very much  :)

Wouldn't scanning the private key with your phone compromise the security of your paper wallet?