Signal Boost: Cake Wallet Team Rolls Bitcoin Lightning Into a DM

Radar Chat, a new messaging app from the team behind Cake Wallet, launched Tuesday combining end-to-end encrypted texts with self-custodial Bitcoin payments over the Lightning Network. Founder Vikrant Sharma said the app lets users send Bitcoin inside chat threads without switching applications or copying wallet addresses. Radar operates as a separate company from Cake Wallet and is available on iOS and Android.

"Rather than reinvent secure messaging from scratch, the team chose to build on one of the most trusted and widely respected privacy technologies available," Sharma told Decrypt. "Many Bitcoin and privacy-conscious users already rely on Signal, so Radar builds on a familiar foundation while adding something that has been missing: native Bitcoin payments inside conversations." Radar uses Signal's open-source protocol for message encryption, though Sharma said Radar is developed independently from Signal and financially supports the Signal project.

"Apps like PayPal and Cash App made sending money easier, but they're centralized services," Sharma said. "They hold your money, they can freeze your account, and they see every transaction you make. Convenience came at the cost of control." Under Radar's setup, users hold their own private keys and receive a recovery seed phrase during onboarding, with an encrypted backup tied to their Signal account available as an additional recovery option.

Payments run over the Bitcoin Lightning Network, a layer-2 system designed to make $BTC transactions faster and cheaper than settling on Bitcoin's base layer. Sharma said Radar is not limited to microtransactions measured in satoshis—or 1/100,000,000 of a full $BTC—and noted the company has successfully tested payments up to $5,000. Transaction capacity is determined by available Lightning Network liquidity rather than limits set by the app, and the product is aimed at everyday payments including buying lunch, splitting expenses, and paying friends.