In the context of Bitcoin, "watch-only" wallets (view-only wallets) are wallets configured to view balances and transactions without having access to private keys. These wallets are useful for monitoring activity at an address without risking compromising funds, as they do not allow signing transactions.
After protecting the private key (12 or 24 words) in metal sheets or washers and we want to add funds without entering the private key all the time, using an NFC sticker with the zpub can be very convenient, this is a tutorial on how to achieve that .
Prerequisites:
Have a Bitcoin wallet and know how to get the zpub.
Download the bluewallet app on your device, it is the app that we will use to open and obtain the information read from the NFC sticker.
Android
IOS
Have NFC sticker (I recommend 540 bytes), search on Amazon, Alibaba or Temu.
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Steps:
Copy the Zpub from the Bitcoin wallet you want.
Ve a NFC tools>Write>add a record> Custom URL/URI
In custom URL/URI enter and copy the zpub, bitcoin:<your Zpub>
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- Bring the NFC sticker closer and save the information
- Check the saved information by bringing the NFC sticker closer, a notification should appear (see image) that redirects you to bluewallet and automatically adds the wallet in Watch-only mode.
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