Researchers and developers explore offline payments on blockchains

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Digital payments remain hard to complete in rural areas or where mobile networks are unreliable, since the obstacle is often connectivity rather than account access. Both traditional and decentralized finance researchers are investigating ways to keep payments functional without a constant internet connection. The article highlights Solana's support for offline transaction signing, which can separate preparing and signing a payment from broadcasting it, though its standard QR-based flow alone does not prevent double-spending. It also cites a June 2026 IEEE paper describing an air-gapped Bitcoin protocol that uses Taproot and QR codes, letting a receiver claim funds with a secret and allowing senders to recover them after a timeout. The author introduces PAT, a Solana-based project intended for a Colosseum hackathon, as part of this emerging work.

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