Using SD cards on Raspberry Pi, we have developed our Blockmesh Networking technology ByteBlock that allows for online to offline to offline then back online data editing transfers without duplication or loss.
This is one of our result screens, we are able to edit and trade crypto data offline as part of an online connected public ledger.
Here is an example of multiple transactions coming through from both of the Raspberry Pi's
This is the peoples router which acts as a miner and holds up the asynchronous updating blockmesh - the other device that looks like a USB carries offline crypto and works offline to offline with any other device on the network. Once it connects back to the peoples router or updates through its paired web app the network ledger refreshes with the offline handshakes that took place.