Cove

Cove is a single-signature Bitcoin wallet for iOS and Android, built on BDK. The app logic is written in Rust with native UI in SwiftUI and Jetpack Compose. It is available on the iOS App Store and Google Play.

The wallet is designed around hardware signing devices. It supports TAPSIGNER and SATSCARD via NFC, and moves PSBTs between phone and signing device using QR codes (including animated BBQr sequences) or virtual drives. Air-gapped workflows keep private keys off the phone entirely.

Cove isn't doing any one new thing. It's bringing all the right pieces together. Coin control on a phone is hard to do well, and I'm proud of how usable it turned out.

—Praveen Perera

Other features include BIP-329 labels for organizing transactions, detailed coin control, custom fee settings, watch-only mode, and a decoy PIN that opens a limited version of the wallet under duress. Users can connect to their own Electrum or Esplora node.

Why fund it?

Good wallet UX for hardware signers is hard to get right on mobile. Most Bitcoin wallets focus on Lightning or multisig; Cove fills a gap for people who want a simple on-chain wallet that works well with Coldcard, Krux, or TAPSIGNER. Praveen has also contributed upstream improvements to rust-cktap, uniffi, and BIP-329 libraries that benefit the broader Rust Bitcoin ecosystem.

OpenSats has been supporting Cove since the fifth wave of Bitcoin grants in July 2024 and has renewed the grant multiple times since.

What's next?

Praveen is working on encrypted cloud backups, onboarding improvements, and sending to silent payment addresses. Other upcoming features include KeyTeleport integration and UTXO lock/unlock with labels.

For a detailed look at earlier progress, see the Advancements in Bitcoin and Lightning Wallets impact report.