Buyer's guide ยท NFC Crypto Kit

NFC crypto wallet card source code: four apps and a card studio

NFC Crypto is the complete source code for a physical-card crypto product under your own brand. It has four apps that share one card format: NFC Crypto, a self-custody wallet for EVM networks, Solana and Bitcoin where a paired NFC card opens the app and confirms each signature; CryptoCard Wallet, where the card holds the PIN-encrypted phrase; NFC Recovery, an offline reader for a card backup; and Card Studio, a desktop tool that programs and tracks the cards. There is no server to run. It is not a hardware wallet, and the pages below say where the card does not protect you.

Buy for $699See NFC Crypto Kit

What you get

  • Four apps in one package

    NFC Crypto (Flutter, iOS and Android), CryptoCard Wallet (Flutter), NFC Recovery (Flutter) and Card Studio (Python, macOS and Windows), plus HTML documentation covering installation, white label, card host, networks, card roles, card format, security, building and updating.

  • Card confirms every signature

    In NFC Crypto the card is a second factor for EVM, Solana, Bitcoin and WalletConnect signatures. You can require the card to open the app, to send, or both. A lost card can be switched off after 72 hours, checked against network time.

  • Card roles and limits

    Owner, Backup and Spender cards. Spender cards have daily limits per chain over a rolling 24 hours, and a payment over the limit needs an Owner or Backup card. Only an Owner card changes the setup.

  • Tap to pay

    Public receive addresses are stored on the card, and Send can fill in an address by tapping the recipient's card. The card never carries keys for this.

  • Phrase backup on the card

    The recovery phrase can be saved on the card, encrypted with a PIN (Argon2id and AES-256-GCM), in one documented format all four apps read.

  • Multi-chain wallet

    EVM networks (Ethereum, BNB, Polygon, Arbitrum, Optimism, Base, Avalanche and custom RPC), Solana and Bitcoin. Send, receive, history, swaps through Jupiter, on-chain Uniswap V2-style routers, 0x and 1inch, Solana staking, WalletConnect, a token approvals manager and app lock.

  • CryptoCard Wallet and NFC Recovery

    CryptoCard Wallet can create a wallet on a blank card, import a phrase onto a card, or use an existing card; the phone is watch-only. NFC Recovery reads a card backup offline, hides the words after 60 seconds and blocks copying and screenshots on Android.

  • Card Studio

    Program, batch-program, clone with a new PIN and byte-for-byte read-back, check a backup PIN and erase cards. It tracks inventory, customers, shipping and activity, exports CSV, and has a simulated reader with sample data.

How you run it as an operator

  • Sell branded cards

    You program, assign and ship your own cards with Card Studio. There is no checkout or payment code in the kit, so selling is up to you.

  • White label for clients

    Name, colours, card host, networks, RPCs, routers and swap fee are set in one file per app, with a test that the native files agree.

  • Optional swap fee

    A fee in basis points on 0x and 1inch routes on EVM chains and on Jupiter routes on Solana, paid to your address. It ships at 0 (off) and is capped at 2 %.

  • Where no fee applies

    Swaps through on-chain Uniswap V2-style routers carry no operator fee.

  • No backend

    The apps use public blockchain endpoints and your optional API keys. The only thing you host is your card domain with two small app-link files.

What it needs to run

  • Flutter 3.41 recommended; the CryptoCard Wallet and NFC Recovery apps use Dart 3.11.1 or newer, so a stated Flutter 3.29 minimum is not enough for them
  • iOS 15.0 or newer (15.5 for NFC Crypto) with Xcode 16 or newer and an iPhone XS or newer for NFC; Android with compileSdk 36 and an NFC-capable phone
  • NFC cards: NTAG215 or NTAG216. NTAG213 is too small for a phrase backup. Cards and printing are not included
  • For Card Studio: Python 3.10 or newer, macOS or Windows, and an ACS ACR122U USB reader for real cards (it also runs with a simulated reader)
  • Your own domain for the card links, serving the apple-app-site-association and assetlinks.json files with your own Apple Team ID and release key
  • Apple Developer Program and Google Play developer accounts to publish; optional API keys such as Reown (WalletConnect), 0x, 1inch, explorers, Alchemy, Helius, Birdeye, CoinGecko and Covalent, each on its own plan

What it does not do

  • It is not a hardware wallet. The cards have no secure element and sign nothing. In NFC Crypto the keys stay on the phone and the card is a second factor the app checks. In CryptoCard Wallet the card stores the PIN-encrypted phrase and the phone opens it in memory to sign.
  • NTAG215 and NTAG216 cards can be copied by whoever holds them, and a copied card works like the original in the app. The PIN protects the backup, but it can be guessed offline, which is why new PINs must be 8 to 12 digits. Copy-proof NTAG 424 DNA cards are the documented production path and are not implemented.
  • Spender limits are rules the app enforces on one phone, not on the card or the blockchain. Another wallet app with the same recovery phrase ignores them. Tokens, swaps and dApp requests always need an Owner or Backup card.
  • Card roles, Spender limits and tap to pay are covered by automated unit and widget tests; the product files record no on-device test results for them. Test your own build with real cards before you sell.
  • CryptoCard Wallet starts on test networks (Sepolia and Solana Devnet). There is no web build. There is no fiat on-ramp, and the server-side enforcement of limits does not exist.
  • The wallet is non-custodial: neither you nor MIKODES can recover a user's phrase. Cards, the reader, the card domain, developer accounts, legal, KYC and money-transmitter compliance and installation service are not included.

Questions

Is it custodial?

No. In NFC Crypto the keys stay on the user's phone and the card confirms each signature. In CryptoCard Wallet the phrase lives only on the card, locked with a PIN. There is no server.

Is it a hardware wallet?

No. The cards have no secure element and sign nothing. Tell your customers exactly that.

Can a card be copied?

Yes. NTAG215 and NTAG216 cards can be copied by whoever holds them. Moving to NTAG 424 DNA cards is described in the documentation but not implemented.

Do I need the card reader to start?

No. Card Studio has a simulated reader, and phones can pair blank cards themselves. You need an ACR122U reader to program cards in bulk.

How does the swap fee work?

You set a rate up to 2 % and your own fee addresses in each app's brand file. It applies to 0x, 1inch and Jupiter swaps only, is off by default and is not a promise of income.

How much does NFC Crypto Kit cost, and what does the licence allow?

$699, one payment, no subscription. One licence, no tiers: any number of projects and clients, a paid SaaS, every line changed. The only limit is reselling or publishing the source code itself. The services you connect bill you directly. See the licence.

Is setup included?

Yes. We install NFC Crypto Kit for you and put in your logo, colours and texts. Bigger changes or new features get a fixed price before we start.

What if it does not work?

Write to us within 14 days. We fix it, usually the same day. If we cannot fix it within 7 days, you get your money back. See the refund policy.