Grant Application — BLINK: Bluetooth-Powered, Privacy-Preserving Payment Infrastructure for Emerging Markets

Community Grants Applications
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:waving_hand: Hey Zcash Community — BLINK is Bringing Shielded ZEC Payments to African Street Markets via Bluetooth

We are BLINK — a live mobile payment app already processing nearly 8 million in transaction volume in Nigeria on iOS and Android. Today we are asking for your support on our Zcash Foundation grant application.

What we do BLINK lets merchants accept crypto payments via Bluetooth Low Energy (BLE) — no QR codes, no manual address entry, no errors. A merchant’s phone broadcasts a beacon, a customer’s phone picks it up automatically, and the payment settles in seconds. We then convert crypto to local currency NGN and deliver it directly to the merchant’s bank account. No P2P. No scams. No frozen accounts.

Why we chose Zcash We evaluated every privacy protocol in the ecosystem. Nothing comes close to Zcash. zk-SNARKs give our merchants mathematically guaranteed privacy not obscurity, not mixing, not a workaround. Shielded balances by default. Selective disclosure for tax compliance. Battle-tested cryptography that our users can trust with their livelihoods.

In Nigeria , a publicly visible transaction history is not just a privacy inconvenience it is a physical safety risk. Merchants with visible on-chain revenue get targeted. BLINK + Zcash changes that.

What this grant funds

  • :blue_circle: Zcash shielded wallet provisioned automatically for every BLINK user at sign-up

  • :blue_circle: First ever shielded BLE crypto payment at a physical merchant location in Africa

  • :blue_circle: Programmatic ZEC-to-local-currency settlement no P2P, no risk

  • :blue_circle: Open-source BLE-to-Zcash reference implementation for the ecosystem

  • :blue_circle: 100+ merchants onboarded onto Zcash privacy rails within 3 months after implementation

What we have already built We are not asking Zcash to fund an idea. We are a live, revenue-generating app with:

  • :white_check_mark: 8 million in processed transaction volume

  • :white_check_mark: 200 completed Bluetooth payments at physical merchant locations

  • :white_check_mark: 300 direct crypto-to-local-currency settlements zero P2P

  • :white_check_mark: Live on iOS App Store and Google Play

  • :white_check_mark: Active merchants across Nigeria

Why this matters for Zcash Zcash has the strongest privacy technology in the industry. What it has lacked is a compelling real-world merchant use case that speaks to people outside the crypto-native community. BLINK is that use case a live app, in the markets that need financial privacy most, ready to deploy Zcash’s technology to users who will genuinely benefit from it every single day.

Every vote for BLINK is a vote for Zcash being used in the real world not just talked about.

We would love your support, your questions, and your feedback. Drop them below :backhand_index_pointing_down:

:link: Download BLINK: [ Blink – Crypto payments at the counter, settled in local currency ]
:link: Grant Application: [https://github.com/ZcashCommunityGrants/zcashcommunitygrants/issues/294\]

Built for the streets of Nigeria. Powered by Zcash.

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Zcash Community Grants Meeting Minutes 05/25/2026
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What is the rate of your users who are using the BLE feature?

Also can you elaborate more on the kyc methods you will be using and how it doesn’t defeat the purpose of Privacy.

Also for Shielded transactions, will the users be operating a self custodial wallet?

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1. What is the rate of your users who are using the BLE feature?

Since launching in April 2026, BLINK has onboarded close to 180 registered users and processed over 22 million in total transaction volume. Of this, 200 transactions have been completed via our Bluetooth Low Energy payment discovery flow, with the remaining volume coming from direct crypto-to-local-currency settlements.

We want to be transparent about what this means. Averaging across our current user base, BLE transaction completion is high on a per-session basis, users who encounter a BLE-enabled merchant complete the payment successfully at a strong rate. The broader adoption curve is tied directly to merchant density rather than user willingness. BLE is a proximity-based feature that requires both the merchant and the payer to be running BLINK simultaneously in the same physical location. As our merchant base grows, BLE utilization grows with it. It is a network effect metric, not a standalone adoption metric.

Every merchant we onboard is a new BLE-enabled payment terminal. Our current focus is merchant acquisition in dense urban markets where foot traffic is high enough to turn BLE into a daily-use feature. We project BLE to account for 40%+ of transaction volume within 6 months of reaching 500 active merchants in a single market.

2. Can you elaborate on your KYC methods and how they do not defeat the purpose of privacy?

Our current KYC implementation uses phone number, email verification and basic identity checks at onboarding. In our next product update, we are integrating Sumsub a globally recognised identity verification platform used by leading fintech and crypto companies worldwide including Binance, Bybit. Sumsub will handle document verification, liveness checks, BVN matching for Nigerian users, and sanctions screening bringing our KYC infrastructure to full regulatory compliance across our target markets.

Here is the critical design principle that ensures KYC does not defeat the purpose of privacy regardless of which KYC layer is active:

KYC happens at the account level not at the transaction level.

When a user signs up for BLINK, their identity is verified once, at onboarding. That identity data is stored securely off-chain. It is never written to the blockchain. It never touches the Zcash shielded transaction layer.

Once a user is onboarded and verified, their on-chain activity is entirely shielded. The Zcash shielded transaction carries zero identity information no name, no phone number, no KYC data. What moves on-chain is cryptographically private by default.

The distinction is straightforward: our KYC layer tells us who our users are. Zcash’s shielded transactions ensure that nobody else not the public, not blockchain analysts, not competitors, not bad actors can see what those verified users are doing with their money after onboarding.

This is the same model used by every legitimate financial privacy system in the world. Your bank knows who you are, but your neighbour, your employer, and a random stranger with a blockchain explorer should not be able to reconstruct your transaction history. BLINK’s KYC satisfies regulatory obligation. Zcash’s shielded transactions protect user privacy from everyone else.

Zcash’s selective disclosure mechanism reinforces this further. Merchants can generate a verifiable proof of specific transactions for tax authorities or auditors when legally required. Disclosure is selective, intentional, and user-controlled never automatic, never systemic. Compliance is possible without privacy being the casualty.

We believe this model, verified identity off-chain, shielded transactions on-chain is the only sustainable path to compliant privacy in regulated African markets. It does not defeat the purpose of privacy. It makes privacy defensible and regulatory legitimate.

3. For shielded transactions, will users be operating a self-custodial wallet?

Yes, and this is a non-negotiable architectural principle for BLINK.

Every user’s Zcash shielded wallet will be fully self-custodial. BLINK never holds, accesses, or controls user private keys at any point. Keys are generated on the user’s device and stored securely using iOS Secure Enclave and Android Keystore hardware-level security that even BLINK’s own backend servers cannot access or reconstruct.

What BLINK provides is the interface and infrastructure around the wallet, the BLE payment discovery, the settlement engine, the local currency conversion, and the onboarding flow. But the wallet itself, and the keys that control it, belong entirely to the user.

This matters enormously in the context of Zcash’s shielded transactions. A shielded wallet controlled by a custodian is not truly private, the custodian can see everything. A self-custodial shielded wallet where only the user holds the keys means that even BLINK cannot reconstruct a user’s transaction history. That is the privacy guarantee we are committed to delivering and it is architecturally enforced, not just promised in a privacy policy.

Our 180 current users are already operating on a non-custodial architecture across Base, Stellar, and Solana. The Zcash shielded wallet integration extends the same principle with the additional privacy guarantees that only Zcash’s shielded transaction protocol can provide.

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Where and who are the majority of your merchants? Because with what I’m seeing, it’s like saying before I can pay for anything I have to wait for the merchant to create a signal then I have to scan for the signal before I can make payment. But I believe with just a QR code, I should not have wallet address error and it’s even faster. The concept is nice oo but for a place like Africa, I believe a more acceptable feature with be thru phone numbers(you can look into that).

And of this 180 users how many have reused the Bluetooth features multiple times.

Why is the information stored off-chain?

I still don’t understand how user privacy is being protected especially with the type of KYC

If the wallet is self custodial

Why do I need a KYC before I can make transactions

Also you said the keys with will be saved on the device so that means if I change devices my keys will be lost?

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1: The majority of our merchants are SME retailers based in Nigeria.

Regarding payment methods, merchants have the flexibility to receive payments via either QR code or Bluetooth, the choice is theirs based on what works best for their context.

On the phone number suggestion: BLINK uses usernames rather than phone numbers as identifiers. This is an intentional design decision to minimise input errors while still providing a familiar, human-readable payment handle but with a lower margin for error.

On Bluetooth adoption, the early data is encouraging. Across our current merchant base of 80, we have processed 200 transactions via Bluetooth, with 62 merchants representing a 77.5% reuse rate having used the feature more than once. This level of repeat engagement at an early stage suggests strong product-market fit for the Bluetooth payment flow among merchants who have tried it.

2: Blockchains are public and permanent. Once data is written to a public ledger, it cannot be edited, hidden, or deleted ever. Storing personal identity information such as your name, email, or verification records on-chain would mean exposing that data to anyone in the world, forever. That is not a risk BLINK is willing to take with your information.

This is precisely why BLINK stores all identity data off-chain, in a secure, encrypted environment with strict access controls. Only authorised systems can read it, and it is never shared beyond what is required for compliance.

As part of our commitment to safety and trust, BLINK will be introducing KYC (Know Your Customer) verification in our upcoming release, powered by Sumsub, a globally trusted identity verification platform used by leading fintech and crypto companies worldwide. This will be a one-time process at onboarding that protects you, protects merchants, and ensures BLINK remains a platform that bad actors cannot exploit. Your identity will be verified once, stored securely, and never touched again unless you request a change.

You get the security of a verified platform without sacrificing your privacy.

3: I still don’t understand how user privacy is being protected especially with the type of KYC
Think of it this way:

KYC confirms your identity. It does not expose your activity.

Those are two completely different things, and BLINK keeps them separated by design.

When you complete KYC on BLINK, you are essentially telling BLINK “I am a real person, here is my ID.” That information goes into a secure, encrypted off-chain database. BLINK sees it. Nobody else ever does not other users, not merchants, not a stranger browsing the blockchain.

That is where KYC ends.

Everything that happens after that every payment you make, every transaction runs through Zcash’s shielded layer. And on that layer, transaction details are completely invisible on-chain. No amounts. No sender. No recipient. A blank wall to anyone looking.

So at no point is your identity linked to your transactions in a way that is visible to the outside world.

The simplest analogy: when you walk into a bank to open an account, they photocopy your ID. That is KYC. But when you later use your card to buy groceries, the supermarket cashier does not see your ID, your account balance, or your transaction history. Those two moments are completely separate.

BLINK works exactly the same way except the transaction privacy is even stronger, because Zcash’s shielded layer makes it cryptographically impossible to trace, not just procedurally restricted.

KYC satisfies the regulator. Zcash protects you from everyone else. Both things are true at the same time.

4:

On KYC:
Even though BLINK is designed with a non-custodial architecture, some features still interact with regulated financial systems especially:

  • instant naira withdrawals,

  • merchant settlements,

  • and fiat payment rails.

KYC is mainly required for:

  • fraud prevention,

  • AML/compliance requirements,

  • reducing scam activity,

  • and protecting the ecosystem as BLINK scales.

The goal is not to control user funds, but to keep the payment infrastructure secure and compliant while still giving users ownership of their wallets.

On private keys and device storage:
If wallet keys only existed locally on one device without recovery infrastructure, losing that device could permanently lock users out of their wallets.

That’s why BLINK includes:

  • wallet export functionality,

  • account-based recovery architecture,

  • and recovery-focused infrastructure planning.

Users can securely sign in on a new device using their login credentials, and their wallet remains intact and accessible.

Our approach is:

  • users control their keys,

  • BLINK does not custody user funds,

  • users can export/import wallets when needed,

  • and users can still recover wallet access across devices through their authenticated account system.

The challenge with self-custodial systems is balancing:

  • ownership,

  • simplicity,

  • recovery,

  • and security

without becoming centralised like traditional financial apps.

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Thank you for submitting your proposal. After careful consideration by the ZCG and a period for community comments on the forum, the committee has decided not to advance this proposal.

We genuinely appreciate the work and dedication you put into your application and hope you’ll continue to participate and contribute to the Zcash community.