Kinglet
Import a watch-only wallet
Export your wallet from your signer and scan it with Kinglet. Compare the fingerprint and the first address with what the signer shows, then import.
Self-custody for Bitcoin XBT
Your keys never touch your phone.
Kinglet is a wallet coordinator for Bitcoin XBT on the BLAKE2b chain. It shows your balances and builds your transactions. Your air-gapped signer signs them, and Kinglet sends. Kinglet never holds a private key.
Pay from your phone.
Sign offline.
Your keys stay on a device that never goes online.
A phone is online all day and runs many other apps, which makes it a risky place for keys. With Kinglet, your iPhone shows your balance and prepares payments. A separate signer that never goes online approves them.
Keys stay on your signer
Kinglet sees your balance and addresses, never your keys. Even someone with your phone cannot move your coins without your signer.
No account
No sign-up, no email, no phone number. No analytics and no tracking. We never see your wallet.
Your own server
Kinglet talks only to the Electrum server you choose. No third-party service, no account.
How it works
Three steps. The keys stay where they are.
Prepare and review
Choose the amount and the fee. If you like, choose the exact coins too. Kinglet shows what you pay and what is left before anything is signed.
Sign air-gapped, then send
Your signer scans an animated QR code from Kinglet and you approve on the signer. Then Kinglet scans the signed transaction back, checks every signature and sends it.
Replay protection
Safe from replay on the SHA256 chain.
Kinglet is built for Bitcoin on the BLAKE2b chain (XBT). Coins from before the fork exist on both chains. A transaction signed the old way could be copied to the SHA256 chain and spend your coins there too. Kinglet refuses to send such a transaction.
Unified sighash
Kinglet asks your signer for SIGHASH_UNIFIED (0x21). The rules on the SHA256 chain reject that hash type, so the transaction cannot be replayed there.
Every signature checked
The review screen tells you what your signer should show. When the signed transaction comes back, Kinglet checks each signature. If one is standard (0x01), it does not send.
Follows the BLAKE2b chain
Kinglet checks that your server follows the BLAKE2b chain, so your balance and history come from the right side of the fork.
Nothing in between
Balances, fee suggestions and broadcasting all go through your own server. No public servers, no third-party services.
What you need
An iPhone, a signer and a server.
An iPhone with iOS 26 or later
Kinglet is free. No account, no in-app purchases.
An air-gapped signer
One that signs with unified sighash (0x21) and exchanges transactions as animated QR codes (UR), such as SeedSigner.
An Electrum server
An Electrum server on a BLAKE2b node, for example Fulcrum on StartOS or Electrs on Umbrel. Setup options
Or nothing at all, for the demo
Try the built-in demo wallet first. It never connects anywhere.
Kinglet supports single-signature wallets for now. Multisig is not supported yet.
Kinglet
Coming to the App Store
Kinglet Wallet is free, has no account and collects no data. The source code goes public on GitHub at launch.