Gas Abstraction for a Blockchain Mobile Health App: WalletConnect UX and Is WalletConnect Safe?

Description

Gas abstraction is a cool feature that allows your health app to sponsor or manage fees, so patients don’t have to “hold ETH to use care.” If you’re looking to get this rolling in 2026, here's how you can do it with WalletConnect, ERC‑4337/7677, and EIP‑7702. Plus, you’ll find a straightforward, up-to-date answer on whether WalletConnect is safe.

TL;DR for decision‑makers

• You can easily set up a HIPAA-compliant mobile user experience that allows users to onboard and sign healthcare intents without worrying about gas fees. You can do this using smart accounts (ERC-4337) or EOAs powered by EIP-7702. Plus, Paymasters are now standardized thanks to ERC-7677 and can seamlessly integrate into your workflow through WalletConnect and EIP-5792. Check out more details here.
• WalletConnect serves as a transport protocol that ensures your sessions are end-to-end encrypted. It employs modern cryptography, offers domain verification via the Verify API, and has gone through an external security audit. It’s safe to use in production as long as you keep your session scopes tight, steer clear of eth_sign, and enforce verification. For in-depth info, visit the specs here.

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Why “gas abstraction” jumped the priority queue in 2025-2026

• EIP‑7702 rolled out with the Pectra mainnet upgrade on May 7, 2025. This update allows Externally Owned Accounts (EOAs) to delegate to audited logic, which paves the way for batching and sponsored fees without making users switch to new smart addresses. For businesses, this means you can maintain a smooth user experience for both legacy EOAs and Account Abstraction (AA) wallets. You can read more about it here.
• The ERC‑7677 introduces a standardized way for wallets to communicate with paymaster web services. Apps can send a paymasterService URL using EIP‑5792’s wallet_sendCalls. From there, wallets can grab stubs, estimate, and then pull in final paymaster data--all while being compatible with EntryPoint v0.6 and v0.7. This is a game changer, cutting down vendor lock-in and minimizing the need for custom integration. Check out the details here.
• WalletConnect has really stepped up its game for mobile users: they’ve launched the Verify API for phishing protection, One-Click Auth (which merges connect and authentication using SIWE and ReCaps), and introduced Link Mode/Deep Linking to reduce lag, especially in those pesky hospital Wi-Fi situations. Learn more about their updates here.

What this means is that a mobile health app can provide a super easy “just tap to consent or pay” experience, all while following the necessary regulations. Plus, your platform can cover gas fees or take stablecoins, so patients don’t have to deal with juggling different network tokens. (docs.walletconnect.network)

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What “gas abstraction” means in a mobile health app

Common Flows You Can Ship Now:

Here are some popular flows that you can easily implement right away:

1. User Registration Flow
   Get your users onboard quickly with a simple sign-up process. Make sure it’s smooth and straightforward.
2. Password Reset Flow
   Help users regain access to their accounts hassle-free by providing an easy way to reset their passwords.
3. Checkout Flow
   Streamline the shopping experience for your customers. A seamless checkout can make all the difference in converting a sale.
4. Feedback Submission Flow
   Encourage users to share their thoughts! Having a straightforward feedback process can give you valuable insights.
5. Profile Update Flow
   Allow users to easily manage their information. This helps keep their accounts updated and relevant.

Feel free to dive in and start shipping these flows now! They’re all great ways to enhance user experience and engagement.

• Zero‑gas onboarding: Make it super easy for new users by letting them link their wallet and sign an EIP‑712 “care intent” or terms message. Your paymaster takes care of the on-chain registration or credential anchor. Check it out here.
• Token‑agnostic payments: When users connect, allow them to request stablecoin payments (pilot wallets are already on board with wallet_pay/CAIP‑358). This way, a co‑pay or subscription takes place in just one step! And don’t worry, if a wallet doesn’t support this, we can still fall back to good old traditional transfers. More info here.
• Consent and audit trails: Simplify things by batching “approve + record consent” in one call using 7702 or AA batching. That means the patient only has to tap once! Plus, your paymaster will handle the gas fees according to your policy. Details can be found here.
• Gasless claims or prior‑auth: Your app can sponsor specific contract interactions, but only for verified provider wallets. This is enforced through allowlists and method scoping, keeping everything secure. Dive into the specifics here.

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WalletConnect UX that works in hospitals

Mobile Networks in Clinics Are Noisy

When it comes to clinics, the hustle and bustle can really impact mobile networks. Here are some things to keep in mind when working in such an environment:

• Signal Interference: With so many devices buzzing around, interference from other mobile networks can lead to dropped calls or slow speeds.
• Construction Materials: The walls and structures in clinics, like metal and concrete, can block signals. This makes it tricky for mobile devices to get a good connection.
• High User Density: Clinics often see a lot of foot traffic. More people using the network can lead to congestion and slow performance.

Tips for Improving Connectivity

1. Wi-Fi as a Backup: Whenever possible, lean on Wi-Fi networks to ease the load on mobile data. They usually offer more stability in tight spaces.
2. Signal Boosters: Consider installing signal boosters in the clinic to enhance coverage, especially in areas with weak signals.
3. Prioritize Critical Communication: Make sure that essential communication tools - like emergency contact systems - get the bandwidth they need.
4. Regular Network Monitoring: Keep an eye on network performance to identify and address any issues quickly.

Remember, working in a noisy mobile environment like a clinic means being proactive about your connectivity solutions!

• Go for deep links instead of universal links if you want smooth app-to-wallet round-trips. Just a heads up, on iOS 17+, the automatic return to browsers is limited, so you might want to tweak your UI to remind users to go back manually if they need to. (docs.walletconnect.network)
• Don't forget to enable Link Mode! It helps carry One-Click Auth and session requests through universal links, especially when WebSocket connections aren't the best. This little trick helps cut down on latency and can even manage those annoying brief offline moments. (docs.walletconnect.network)
• Last but not least, make sure to set up unique redirect URIs for each platform--web, iOS, and Android. This helps prevent cross-device hijacking when someone scans a QR code on one device but then approves on a different one. (docs.walletconnect.network)

Session Scoping Matters:

When it comes to managing sessions in your applications, the concept of session scoping becomes really important. Here’s why it matters and how to get it right:

What is Session Scoping?

Session scoping is all about defining the lifespan and visibility of your session data across different parts of your application. Basically, it dictates where your session data can be accessed and how long it sticks around.

Why You Should Care

Understanding session scoping can help you:

• Enhance Security: By limiting session data access, you reduce the risk of unauthorized access.
• Improve Performance: Proper session management can lead to better performance by making sure you're not holding onto unnecessary data.
• Simplify Debugging: When you know exactly where your session data lives, tracking down issues becomes a breeze.

How to Get It Right

Here are a few tips to effectively manage session scoping:

1. Use Appropriate Scope Levels: Depending on your app’s architecture, choose between singleton, session, or request scopes. Each has its own use cases.
2. Limit Session Lifespan: Set a reasonable expiration time for your sessions. This keeps your data fresh and reduces clutter.
3. Be Consistent: Stick to a consistent session management strategy throughout your application to avoid confusion.
4. Document Your Approach: Make sure to document your session scoping strategy. This way, anyone jumping into your project can understand how things work.

Conclusion

Getting session scoping right is crucial for building efficient, secure applications. By paying attention to how you manage your sessions, you'll not only enhance your app's performance but also make life easier for yourself and your team. So, the next time you're working on session management, keep these points in mind!

• Please make sure to request only the essential methods and chains through Namespaces. Skip the wildcards and focus solely on production chains. Here’s an example for reference: (specs.walletconnect.com).
• It’s crucial to implement the Verify API on both the wallet and app sides. This way, users can see those handy domain-verified banners, and we can default-block any THREAT classifications. Check it out here: (docs.walletconnect.network).

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Is WalletConnect safe in 2026?

Short answer: Absolutely! It’s a secure transport since it’s end-to-end encrypted and regularly audited. However, you’ll need to ensure your app maintains good session hygiene. Here’s the scoop:

• Protocol Security: Clients create a shared key using X25519 and HKDF, then encrypt it with ChaCha20‑Poly1305. The cool part? Relays only see the encrypted ciphertext. When clients authenticate with relays, they use JWTs linked to did:key (Ed25519). You can check out more details here.
• Network Behavior: Messages are sent through a pub/sub system based on “topics,” and they're cached on the server side with a TTL for offline delivery. Plus, push notifications can alert users to sign. If you want specifics, head over here.
• Audit: WalletConnect v2 went through an independent assessment by Trail of Bits. All the findings were addressed and tracked in a transparent manner. You can read about it here.
• Phishing Defense: The Verify API checks for UNKNOWN, INVALID, and THREAT domains, giving wallets a heads-up to warn or block anything fishy before a session starts. Make sure your app registers metadata and keeps its domains in check. More info can be found here.

Residual risks hang out at the app layer--think drainers, perplexing signatures, or overly broad permissions. You can tackle these by: disabling eth_sign, using EIP‑712 typed data with clearly defined fields and nonces, keeping namespaces tightly scoped, setting short session expiries, and implementing contract allowlists. Check out more about it here: (eips.ethereum.org).

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Two reference architectures for gas abstraction

A. “Works with any wallet” via EIP‑7702 + sponsored calls

When users have EOAs (like MetaMask, Coinbase Wallet, Ledger, and so on), the 7702 protocol allows these wallets to temporarily delegate to contract code. This feature makes it easy to batch actions together and also enables sponsorship:

1. The app sets up a wallet_sendCalls request that includes the paymasterService capability.
2. The wallet reaches out to your ERC‑7677 paymaster web service to get the sponsor fields sorted out.
3. The user signs off; the bundler submits everything, and the paymaster takes care of the payment.

• Why choose this option? It doesn't require any smart-account migration, so there's hardly any hassle for regular wallets. Plus, it's a solid choice for regulated processes that need to keep the patient's existing address intact for tracking purposes. You can read more about it here.

B. “Programmable from day one” via ERC‑4337 smart accounts

Setting Up a Smart Account with ERC-7677

Alright, let’s get your smart account up and running! You can choose from options like Safe, Kernel, or the Coinbase Smart Wallet. Once you’ve got that sorted, you’ll want to dive into ERC-7677. Here’s how to do it using providers like Coinbase Paymaster or Pimlico:

1. Choose Your Smart Account:
   Pick one of the following smart accounts:
   • Safe
   • Kernel
   • Coinbase Smart Wallet
2. Set Up the Account:
   Follow the steps for your chosen wallet. Make sure you jot down any recovery phrases or keys - you won’t want to lose those!
3. Integrate ERC-7677:
   To use ERC-7677, make sure your wallet supports this standard.
4. Select a Provider:
   Now, you’ll want to connect with a provider. You can go for:
   • Coinbase Paymaster
   • Pimlico
5. Complete the Setup:
   Follow the specific instructions provided by the service to link everything together.

And just like that, you’ll be all set to enjoy the benefits of your new smart account!

• Standardized RPC: first run pm_getPaymasterStubData to estimate, then go ahead with pm_getPaymasterData to execute.
• Mature SDKs: check out permissionless.js, as well as some provider examples, and don't forget, you can fork the paymaster contracts! (docs.cdp.coinbase.com)

Go with B if you're looking for multi-sig guardians, session keys, or intricate policies. Choose A when you want quick compatibility with EOAs and a sponsored user experience.

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Concrete snippets you can adapt

1) Request Only What You Need (WalletConnect Namespaces)

When working with WalletConnect, it’s super handy to ask for just the information you actually need. This helps streamline the process and keep everything efficient. By using Namespaces, you can define what data you’re requesting, making your interactions cleaner and more straightforward.

Here’s how it works:

• Identify the specific data: Before sending a request, take a moment to think about what exactly you need.
• Utilize Namespaces: Use the WalletConnect Namespaces feature to specify those needs. This allows you to filter out unnecessary data and focus only on what's relevant to you.

This approach not only keeps your requests tidy but also enhances the performance of your application. By being precise, you ensure a smoother experience for your users!

{
  "requiredNamespaces": {
    "eip155": {
      "chains": ["eip155:8453"], 
      "methods": [
        "eth_sendTransaction",
        "eth_signTypedData" 
      ],
      "events": ["accountsChanged", "chainChanged"]
    }
  },
  "optionalNamespaces": {}
}

• Rationale: Focus on the mainnet for now; skip eth_sign; use typed data for consent; keep events to a minimum. (specs.walletconnect.com)

2) EIP‑5792 wallet_sendCalls with an ERC‑7677 paymaster service

When it comes to initiating transactions on Ethereum, the EIP‑5792 standard introduces the wallet_sendCalls method, which simplifies how wallets can batch various calls together. This is pretty cool because it streamlines the process for users. Now, let’s dive into how this works with an ERC‑7677 paymaster service.

What’s the Deal with EIP‑5792?

EIP‑5792 allows wallets to send multiple calls in one swoop instead of doing them one by one. This saves time and gas fees, making it a win-win for everyone involved.

How Does the ERC‑7677 Paymaster Fit In?

The ERC‑7677 paymaster service plays a key role here. It enables users to pay for their transactions in a more flexible way, often covering the gas fees. This is especially helpful for new users or those who might not have ETH on hand.

Breaking It Down

Here's a quick breakdown of how it all works:

• Batch Calls: Users can send a batch of calls using wallet_sendCalls, which makes interactions more efficient.
• Gas Payment: With the ERC‑7677 paymaster, users can have the option to pay for their gas fees through different tokens or even have them subsidized.
• User Experience: By merging these two components, the whole experience becomes smoother, allowing more users to engage with Ethereum dApps without the usual hurdles.

Conclusion

In summary, the combination of EIP‑5792’s wallet_sendCalls and the ERC‑7677 paymaster service is a game changer in the Ethereum ecosystem. It not only enhances transaction efficiency but also makes it easier for users to dive into the blockchain world without worrying too much about gas fees.

[
  {
    "version": "1.0",
    "chainId": "0x2105", 
    "from": "0xPatient",
    "calls": [
      {
        "to": "0xConsentRegistry",
        "data": "0x<encodeFunctionData(consent(patientIdHash, policyId))>"
      }
    ],
    "capabilities": {
      "paymasterService": {
        "url": "https://paymaster.yourdomain.com/api/erc7677",
        "context": {
          "policyId": "care-consent-v1",
          "budgetId": "patient-onboarding-2026Q1"
        }
      }
    }
  }
]

• It’s compatible with AA wallets and can connect to EOAs through 7702. The backend proxy keeps your provider API keys safe and makes sure your business rules are followed. Check it out here: (eips.ethereum.org)

3) Example EIP‑712 Consent Message (Displayed in Wallet)

Here's a look at what an EIP‑712 consent message might look like when you see it in your wallet. This message is meant to clearly explain what you're consenting to before you take any action.

{
  "domain": {
    "name": "MyDApp",
    "version": "1",
    "chainId": 1,
    "verifyingContract": "0x1234567890abcdef1234567890abcdef12345678"
  },
  "message": {
    "user": "0xabcdefabcdefabcdefabcdefabcdefabcdefabcd",
    "action": "approve",
    "amount": "1000",
    "nonce": "123456789"
  },
  "primaryType": "Consent",
  "types": {
    "EIP712Domain": [
      { "name": "name", "type": "string" },
      { "name": "version", "type": "string" },
      { "name": "chainId", "type": "uint256" },
      { "name": "verifyingContract", "type": "address" }
    ],
    "Consent": [
      { "name": "user", "type": "address" },
      { "name": "action", "type": "string" },
      { "name": "amount", "type": "uint256" },
      { "name": "nonce", "type": "uint256" }
    ]
  }
}

This JSON structure gives you the rundown of the message. It includes crucial details like the user’s address, the action they’re about to take, the amount involved, and a unique nonce for added security. Always remember to read these messages carefully before signing!

{
  "domain": {
    "name": "YourHealthApp",
    "version": "1",
    "chainId": 8453,
    "verifyingContract": "0xConsentRegistry"
  },
  "primaryType": "Consent",
  "types": {
    "EIP712Domain": [
      {"name":"name","type":"string"},
      {"name":"version","type":"string"},
      {"name":"chainId","type":"uint256"},
      {"name":"verifyingContract","type":"address"}
    ],
    "Consent":[
      {"name":"patientIdHash","type":"bytes32"},
      {"name":"policyId","type":"string"},
      {"name":"expiresAt","type":"uint256"},
      {"name":"nonce","type":"uint256"}
    ]
  },
  "message": {
    "patientIdHash": "0x<saltedHashOfInternalID>",
    "policyId": "care-consent-v1",
    "expiresAt": 1772457600,
    "nonce": 1
  }
}

• EIP‑712 creates prompts that are easy to read for humans and protects against replay attacks. Remember, it's best not to include any PHI in the message--stick with pseudonymous hashes instead. (eips.ethereum.org)

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Paymaster choices and policy hardening

You’ve got some solid, reliable choices:

• Coinbase Paymaster: This one's all about being ERC‑7677 compliant and comes packed with a production bundler along with handy allowlists. Plus, they offer promotional gas credits on Base to speed up your pilot projects. Check out more details here.
• Pimlico: They’ve got some super cool open tooling called permissionless.js, making it easy to verify and manage Singleton paymasters with an ERC‑20 mode. They also provide templates for ERC‑7677 proxy services, which is a win for anyone looking to cover multiple chains. Dive into their stuff on GitHub.
• Biconomy: Their ERC‑7677 endpoints are up and running; SDK support is getting there too--meanwhile, direct JSON‑RPC is already working like a charm. Get the lowdown here.

Policy Tips for Healthcare:

Navigating the healthcare landscape can be tricky, but with the right strategies, you can make a real difference. Here are some handy tips to keep in mind:

1. Stay Informed

Make it a priority to keep up with the latest healthcare policies and regulations. Subscribe to trusted newsletters, follow industry leaders on social media, and join relevant forums. Knowledge is power!

2. Engage with Stakeholders

Building relationships with key stakeholders is crucial. Whether it’s patients, providers, or policymakers, understanding their perspectives can help shape effective policies. Don’t hesitate to start conversations and gather insights.

3. Focus on Data

Utilize data to back up your policy decisions. Analyze healthcare trends and outcomes to support your strategies. Data can help illustrate the need for change and inform better decision-making.

4. Advocate for Equity

Championing health equity should be at the heart of any healthcare policy. Ensure that all demographics have access to quality care, regardless of socioeconomic status. Advocate for policies that level the playing field.

5. Be Flexible

The healthcare environment is always changing. Be ready to adapt your policies as new information and scenarios arise. Flexibility can often lead to innovative solutions.

6. Collaborate

Team up with other organizations and groups that share similar goals. Collaboration can amplify your efforts and result in a bigger impact. Plus, it’s a great way to share resources and knowledge.

7. Measure Success

Establish clear metrics to assess the effectiveness of your policies. Regularly evaluate and tweak your strategies based on these metrics to ensure you're on the right track.

8. Communicate Clearly

Effective communication is key. Make sure your messages are clear, concise, and accessible to your audience. Use a variety of formats, like social media, newsletters, or community meetings, to reach everyone.

9. Invest in Training

Don’t forget about training and education! Ensure that your team is up to date on the latest practices and policies. Investing in their growth is investing in the future of your healthcare initiatives.

10. Foster Innovation

Encourage creative thinking within your team. New ideas can lead to groundbreaking policies that improve patient care and healthcare delivery. Support an environment where innovation can thrive.

By keeping these tips in mind, you’ll be better equipped to navigate the complex world of healthcare policy and make a real impact. Happy policymaking!

• We've set up contract and method allowlists at the paymaster layer, and anything outside that gets a hard pass.
• There are rate limits for each wallet and device, and we’re enforcing budgets per call through context.
• For failover, if the main paymaster says no, we smoothly switch to a fallback sponsor or give the user a nudge to cover the gas. We designed it to be safe-to-stop (STS), so those crucial flows can keep moving without a hitch. Check out the details here: (docs.erc4337.io)

Security Note:

Make sure you're keeping up with the latest EntryPoint versions and bug fixes. Remember, template paymasters get updated too--so it’s a good idea to verify that your paymaster repositories and the docs maintained by EF are reflecting the versioned behaviors. Check it out here: github.com.

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Compliance and privacy posture for U.S. health apps

• So, here’s the deal: HIPAA doesn’t apply to every single consumer health app. It really depends on whether you’re considered a covered entity or a business associate. If HIPAA isn’t in the picture, don’t worry--the FTC Act (and maybe the Health Breach Notification Rule) still come into play. Make sure you’re thinking about privacy-by-design no matter what. (ftc.gov)
• A quick tip: steer clear of putting PHI on public chains. Keep any on-chain data pseudonymous (like using salted hashes), and store that PHI off-chain, like on a FHIR server or a secure cloud, under a Business Associate Agreement if you’re a BA. Also, consider WalletConnect payloads as “sensitive”--even though they’re end-to-end encrypted. (hhs.gov)
• If a patient sends their ePHI to a third-party app that isn’t a BA, just a heads up--HIPAA protections don’t stick around. It's super important to educate users about this and keep track of those consent flows. (hhs.gov)

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Implementation checklist (engineer‑ready)

• WalletConnect hygiene
  • Make it a rule to use the Verify API and block THREAT right out of the gate.
  • Namespaces: only ask for the chain(s)/methods you actually need; and keep those expiry times short (7 days max).
  • Steer clear of eth_sign; go for eth_signTypedData instead for clearer messages. Don’t forget to include the domain and purpose in your messages. (docs.walletconnect.network)
• Mobile experience
  • Use deep links by default; make sure to design for manual returns on iOS 17 and up; and turn on Link Mode for those native-to-native interactions. Check out the details here: (docs.walletconnect.network)
• Gas abstraction
  • Integrate ERC‑7677 using a backend proxy; make sure to pass paymasterService in EIP‑5792 calls and log those policy decisions.
  • Begin with Base for credits and tools, then expand to other chains as provider support rolls in. (eips.ethereum.org)
• Observability
  • Keep an eye on session scopes, rejection rates (you'll want to verify those UNKNOWN/INVALID ones), and any paymaster declines.
  • Set up alerts for any unexpected methods, chains, or contract addresses at the wallet/policy level. Check it out here: (docs.walletconnect.network)

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Emerging practices to watch in 2026

• wallet_pay (CAIP‑358): This is a cool connect-and-pay standard that lets you check out with just one tap across different chains and wallets. WalletConnect is taking the lead on this with some Certified requirements. Right now, it's in pilot mode behind a feature flag. You can read more about it here.
• One-Click Auth everywhere: We're talking about a neat combo of SIWE + ReCaps for smooth capability delegation during connection. When you mix this with Verify + Link Mode, you get a native user experience that really shines. Check out the details here.
• Certified programs: WalletConnect's Certified program has expanded to include apps and institutions, which means there's more pressure in the ecosystem for safer defaults and valid domains/contracts. Don't forget to use these badges while allowlisting in your wallet and during QA checks. Dive deeper here.

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What about adoption?

By late 2024, third-party telemetry revealed that there were over 100 million UserOps and a lot of paymaster usage happening. Then, in 2025, things really started to come together with infrastructure and standards maturing--think ERC-7677, 7702, and provider credits. What does this mean for you? It means you can now create gasless user experiences without needing custom setups. Just make sure to validate these insights against the chains and providers you’re working with, and consider running a capped pilot in Base before you scale things up. Check out the full details here.

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A minimal, safe‑by‑default flow you can ship in a quarter

1. You start by connecting with One‑Click Auth, and everything checks out as VALID.
2. The app suggests kicking off a session using eip155:8453 and offers methods like {eth_sendTransaction, eth_signTypedData}.
3. The user gives the green light to a typed “care consent” (don’t worry, it doesn’t include any PHI).
4. Next, the app takes action by calling wallet_sendCalls with paymasterService.
5. The wallet sorts through paymaster stubs to get the final data; then, the bundler jumps in to submit it, and the paymaster takes care of the payment.
6. Finally, store the off‑chain PHI while only anchoring pseudonymous hashes on‑chain for auditing purposes. (docs.walletconnect.network)

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Bottom line

• WalletConnect is super secure as a protocol, and they've rolled out some cool features that businesses really need, like Verify, One‑Click Auth, Link Mode, and Certification. The real risk comes from session scope and the signing experience. You can tackle this by using typed messages, strict namespaces, and domain verification. Check it out here: (walletconnect.com)
• Gas abstraction is finally ready for the big leagues! You can choose between ERC‑4337 or 7702 based on your wallet setup. Just implement ERC‑7677 once, and you can swap providers without breaking a sweat. It’s a good idea to start on Base to minimize costs and timelines. More info here: (eips.ethereum.org)

If you're looking for an architecture review or a quick two-week spike to whip up a working pilot (complete with consent, gasless calls, Verify, and audits), 7Block Labs has a solid template ready for healthcare apps.