You hold the keys
Your wallet is made from 12 random words on your device. Whoever has those words controls the funds. Blitz and Spark cannot move them.
What self-custody means
A self-custody Bitcoin wallet means you hold the keys. Not a bank, not an exchange, not Blitz. Your 12-word seed phrase is the backup that lets you recover the wallet.
The basics
What self-custody means
Think of a safe you own. Only your key opens it. Blitz helps you use it, but cannot open it for you.
No freeze, no reverse
With custodial apps, a company can freeze or reverse a payment. With self-custody, only you can send. Like cash in your pocket.
Recover anywhere
Enter the 12-word backup in Blitz or the open-source spark-recover tool. Your funds reappear. If you lose the backup, you lose the funds.
Custodial vs self-custodial
How they compare
| Question | Custodial (exchange/bank) | Blitz (self-custodial) |
|---|---|---|
| Who holds the keys? | Company | You, with 12 words |
| Can they freeze your account? | Yes | No, only you can send |
| If company closes? | Wait for withdrawal | Restore on another Spark compatible wallet or our open-source tool |
| If you lose backup? | Reset password | Funds are lost, so back up carefully |
| Privacy | Account and ID on file | No ID needed to create a wallet |
How to do it right
How to back up your wallet
Write it on paper
Copy the 12 words in order by hand and double check them. Keep the backup in a secure place.
Never share or screenshot
Anyone with the words can take the funds. Do not email, save to the cloud, or share them. Blitz will never ask for them.
Test your recovery
After backing up, try restoring on another device, then wipe it. If it works once, it will work when you need it.
Add a PIN & biometrics
Blitz lets you lock the app with PIN, Face ID or fingerprint. Your wallet secret stays encrypted on device.
FAQ
Common questions
Can Blitz help if I lose my backup?
No. That is the point of self-custody. If Blitz could recover without the backup, it could also move your money without you. Keep the 12 words safe.
Is self-custody harder to use?
No. Save your 12 words once. After that, Blitz works like any other payments app. You can pay contacts, send gifts, and use pools the same way.
What about large amounts?
Blitz is considered a "hot wallet". This means while your keys are yours, it's meant to be a daily spending wallet insted of a savings wallet.