Post
Topic
Board Development & Technical Discussion
Re: Offline Crypto Transactions – No Internet, Fully Blockchain-Valid
by
aristotelsato
on 04/08/2025, 09:00:42 UTC
I’ve recently completed successful testing of a prototype that enables sending Bitcoin transactions between mobile phones — with no Internet connection, no Wi-Fi, no cellular data, no Bluetooth.

By any chance, do you use screen (that show QR code) and camera (which scan QC core)  ?

you can check it Here Also ---> https://mempool.space/testnet/tx/1b500a8205b8d317c79b39a1e8025135d50413afe3c6a5901fbfce985da1e5d8

The transaction is valid on-chain, tested on Bitcoin testnet, and the signature is 100% verifiable with no risk of double-spend.
Key features:
✔ Fully compatible with Bitcoin transaction structure (validated on testnet) 
✔ Secure: no replay/double-spend vulnerability 

For these points, IMO it's not worth to mention since your usual offline TX does same thing.
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Thanks for your question — and it’s a good one.

No, I’m not using QR codes or camera scanning between devices.

What I’m building is not a cold-wallet model or standard airgapped QR flow. It’s something more direct and unconventional, where data is exchanged between devices without traditional I/O or connectivity (no QR, no Bluetooth, no NFC, no Wi-Fi).

The fact that the transaction is valid is just a byproduct — the real innovation is in how the TX gets from device A to B. and it gets Globally! not like 10 meters away!

I understand your point — but I’d argue that “offline TX” usually means just signing offline and broadcasting later. What I’ve done includes transmission too — without any external connection.

That’s what I believe is the novelty here.

I’ll release more details in a controlled way, but happy to answer conceptual questions