What Aura can do, and what it cannot

The primitives, named

You should not have to take “bank-grade encryption” on faith. These are the actual algorithms, so you can judge them yourself.

Phrase generation

BIP-39, 128 bits of entropy from the device’s cryptographic random source, encoded as twelve words.

Address derivation

BIP-32 and BIP-44 hierarchical derivation, at each chain’s own registered coin type and path — not one path reused everywhere.

Phrase encryption

XSalsa20-Poly1305 authenticated encryption (TweetNaCl secretbox), so a tampered ciphertext fails to open rather than decrypting to garbage.

Key derivation

PBKDF2-HMAC-SHA512 over your passcode and a per-wallet random salt. The passcode is not stored; only a verifier that cannot be reversed.

Passcode checking

Constant-time comparison, so the time a wrong passcode takes to fail tells an attacker nothing about how wrong it was.

Storage at rest

The platform keystore — the Keychain on iOS, backed by the Secure Enclave, and the Keystore on Android.

Cloud backup

The same XSalsa20-Poly1305 envelope under a separate PBKDF2-HMAC-SHA512 passphrase of your choosing, sealed before it is written to your own cloud.

Transport

TLS to every RPC, price and router endpoint. Nothing about your wallet is sent in the clear.

Exactly what leaves your device

A wallet that spoke to nothing would show you no balances and could broadcast no transactions. So things do leave your phone — and you deserve the list rather than a slogan. Each row below says what goes out and who receives it.

• Your addresses, to read the chain

  Public RPC nodes

  Balances, token holdings, history and fee estimates all come from each network’s own nodes, which have to be told which address you are asking about. Every wallet works this way.

• Your addresses, to a balance indexer

  Aura

  Checking 47 EVM chains one call at a time is slow, so the app can ask our indexer for all of them at once. It receives public addresses and nothing else, and the app falls back to scanning on device if the indexer is unavailable.

• A swap you are pricing

  Jupiter, LI.FI, Uniswap, 0x, Relay

  The token pair, the amount and the address that would sign, sent straight from your phone to each router. These requests do not pass through us — we never see a quote you asked for.

• A swap you actually submitted

  Aura

  Once you have signed and broadcast, the app registers the transaction so it can follow a cross-chain hop to the far side and tell you when it lands. This is status tracking after the fact, not custody or approval.

• A push token and the addresses to watch

  Aura

  Only if you turn on notifications for incoming transfers. We store the device token and the addresses you asked us to watch, so the server can notice a deposit and tell your phone. Turn it off and the record goes with it.

• Which tokens to price

  Price and metadata providers

  Symbols and contract addresses, to fetch a rate and a logo. Not balances, and not amounts — the same request happens whether you hold one dollar or a million.

One thing worth being plain about: an address is public by design. Once you have used one, anyone with a block explorer can see its balance and its history. Sending an address to an indexer does not expose anything the chain was keeping secret. What matters is that nothing able to spend from that address ever leaves your phone.

The encrypted backup, and its honest tradeoff

Paper survives a dead phone but not a flood. If you want a second copy, Aura can seal your wallet into a single file and put it in the cloud account you already have.

1. 01

   You choose a passphrase

   Separate from your passcode, and not derived from it. Aura never sees it and cannot help you guess it later.

2. 02

   The file is sealed on your phone

   XSalsa20-Poly1305 under a PBKDF2-HMAC-SHA512 key stretched from that passphrase. It is already ciphertext before it moves.

3. 03

   It is written to your own cloud

   Your iCloud or your Google Drive, under your account. Aura keeps no copy and stores no key that would open one.

The tradeoff is real and worth stating: a strong passphrase you forget makes the backup as useless as no backup at all, and a weak one turns your cloud account into the weakest wall around your money. Choose accordingly, and keep the paper either way.

What good cryptography cannot do for you

Every wallet page you have read lists its strengths. This is the other half. None of the algorithms above help with any of the following, and pretending otherwise is how people lose money.

A phrase that is gone

Lose the paper and lose the phone, and the coins stay on the chain where everyone can see them and nobody can move them. This is not a policy we could relax.

A signature you were tricked into

A transaction you approved is valid, whatever you believed it was doing. Read what you are signing, especially token approvals, which can keep spending long after you close the app.

A phone somebody else controls

Malware with your unlocked screen is you. Keep the OS current, install from the official stores only, and treat a jailbroken or rooted device as unsuitable for holding money.

A token that was always a trap

Anyone can mint a token, name it after a real one, and make it unsellable. Aura will show you what you hold; it cannot tell you the project behind it is honest.

A bridge or router failing

Cross-chain hops depend on the protocol you routed through. Aura shows you the route and the provider precisely so the risk is yours to see, not ours to hide.

Somebody who knows your passcode

The whole security of the sealed phrase reduces to a secret you can remember. Do not reuse the one that unlocks your phone, and do not enter it where someone can watch.