Hydra Mobile SDK for Android & iOS

[Proposal setup] Proposal title

Please provide your proposal title

Hydra Mobile SDK for Android & iOS

[Proposal Summary] Budget Information

Enter the amount of funding you are requesting in ADA

80000

[Proposal Summary] Time

Please specify how many months you expect your project to last

5

[Proposal Summary] Translation Information

Please indicate if your proposal has been auto-translated

No

Original Language

en

[Proposal Summary] Problem Statement

What is the problem you want to solve?

Mobile devs lack a native, well-documented SDK to open/join Hydra Heads and build/sign/broadcast transactions from Android/iOS. This blocks real-time, low-fee mobile dApps on Cardano

[Proposal Summary] Project Dependencies

Does your project have any dependencies on other organizations, technical or otherwise?

No

Describe any dependencies or write 'No dependencies'

No Dependencies

[Proposal Summary] Project Open Source

Will your project's outputs be fully open source?

Yes

License and Additional Information

MIT License

[Theme Selection] Theme

Please choose the most relevant theme and tag related to the outcomes of your proposal

Developer Tools

[Campaign Category] Category Questions

Mention your open source license and describe your open source license rationale.

We will release the project under the MIT License, a permissive open-source license that maximizes adoption, encourages community contributions, and allows both commercial and non-commercial use. MIT is widely recognized and compatible with most ecosystems, ensuring broad integration potential. This approach aligns with Cardano’s open innovation goals by enabling forkability, transparency, and reuse.

How do you make sure your source code is accessible to the public from project start, and people are informed?

From day one, all code will be hosted in a public GitHub repository with clear README and contribution guidelines. We will use milestone-based commits, tagged releases, and issue tracking to ensure transparency. Updates will be shared through Cardano forums, Discord, and Twitter so the community can follow progress and test early versions.

How will you provide high quality documentation?

We will provide comprehensive user and developer documentation including setup guides, API references, and architecture diagrams. Documentation will follow a clear, structured format using Markdown and Docusaurus for easy navigation. Examples, tutorials, and recorded walkthroughs will be included, and all docs will be versioned alongside code to remain accurate with each release.

[Your Project and Solution] Solution

Please describe your proposed solution and how it addresses the problem

We will deliver an open-source Flutter SDK that makes Hydra easy to use in mobile applications. Developers will have a simple, well-documented API to connect to a Hydra node, open or join a Head, send and receive payments, and close the Head when finished. The SDK will include example apps, ready-to-use code snippets, and step-by-step documentation so teams can integrate quickly without having to understand low-level networking or protocol details.

Key inclusions:

• Flutter SDK with a consistent, easy-to-use API.
• Example “micropayments” and streaming apps showing complete end-to-end flows.
• Setup scripts and clear guides for local/test environments.
• Optional wallet bridge adapters for seamless mobile signing flows.

Addressing the problem:

Currently, Flutter developers have no direct, well-supported way to build Hydra-powered mobile apps. This SDK removes that barrier by:

• Reducing complexity – one unified API replaces bespoke networking and message handling.
• Cutting time-to-market – ready-made examples and documentation help teams launch faster.
• Improving reliability – built-in connection handling, error recovery, and sensible defaults ensure stable integration.
• **Enabling modern mobile UX **– low-latency, low-fee Hydra transactions for use cases like gaming, content streaming, in-app tipping, and real-time collaboration.

[Your Project and Solution] Impact

Please define the positive impact your project will have on the wider Cardano community

Value to the Cardano Community:

This project delivers real-time, mobile-first UX to Cardano via a dedicated Flutter SDK for Hydra. With sub-second transactions inside Hydra Heads, games can settle every move, creators can stream micro-payments, and collaborative apps can update instantly. This transforms casual interest into active on-chain use—boosting daily active users, transaction volume, and demand for Cardano-native mobile experiences.

How We Will Measure Impact:

• Quantitative: SDK downloads, GitHub stars/forks, number of live apps, on-chain Hydra transaction volume.
• **Qualitative: **Developer feedback, integration case studies, and community adoption stories.
• Benchmarks: Reduction in integration time (measured through partner teams) and growth in Hydra-powered mobile dApps.

How We Will Share Outputs:

All deliverables SDK, wallet adapters, example apps, and documentation, It will be open source from day one. Code will be hosted on a public GitHub repository with tagged releases and clear contribution guidelines. Progress and opportunities for collaboration will be shared through Cardano forums, Discord, Twitter, and developer workshops, ensuring broad awareness and reusability across the ecosystem.

[Your Project and Solution] Capabilities & Feasibility

What is your capability to deliver your project with high levels of trust and accountability? How do you intend to validate if your approach is feasible?

Dextr Labs – https://dextrlabs.com/ – is a team of 25 experienced developers and blockchain engineers with deep expertise in building secure, scalable Web3 infrastructure. Over the past two years, we have delivered multiple production-grade blockchain products with a 100% on-time delivery rate, maintaining strong client relationships through consistent quality and transparent processes.

Our track record includes Zodor (https://www.zodor.io,,) a Real-World Asset (RWA) tokenization platform, and BePay (https://bepay.money) a stablecoin-powered payment solution. These projects demonstrate our capability to integrate complex smart contracts, optimize for mobile experiences, and deliver cross-platform interoperability—skills directly applicable to building the Flutter SDK for Hydra.

We bring proven experience in:

Developing SDKs and cross-platform tools for mobile and web environments.

Integrating blockchain protocols into user-facing applications with clean, maintainable APIs.

Running open-source projects with milestone tracking and contribution management.

[Milestones] Project Milestones

Milestone Title

Project Initiation

Milestone Outputs

**Landscape Review: **Assessment of existing Hydra tooling and mobile feasibility (Flutter), identification of gaps and opportunities.

Technical Assessment: hydra-node interfaces (WS/HTTP), connectivity considerations (TLS, authentication), and mobile constraints (backgrounding, offline handling, retry logic).

Requirements Documentation: Functional and non-functional specifications for SDKs, wallet bridges, sample apps, and documentation.

Acceptance Criteria

Detailed analysis capturing technical hurdles (e.g., WS messaging, signing flows, state synchronization) and resource requirements.

Explicit project boundaries, success metrics, and delivery timelines.

Risks such as platform-specific WS quirks identified with proposed mitigation strategies.

Evidence of Completion

Launch Document committed to the public repository.

Requirement Document committed to the public repository.

Delivery Month

1

Cost

20000

Progress

20 %

Milestone Title

Architectural Planning

Milestone Outputs

Client Workflow: Connect → open/join Head → commit → in-head payments → close/fan-out (covering both normal operation and failure modes).

**API/Integration Points: **hydra-node message schema, wallet-bridge options (deeplink/webview), and tx-build adapters (Dart for Flutter).

Security & Scalability: TLS, key handling, permissioning, back-pressure management, and reconnection policies.

Risk Evaluation: Platform-specific constraints (e.g., backgrounding, network transitions) with documented mitigations.

System Architecture Blueprint including:

Diagrams of SDK module layout, message pipelines, state machines, error handling flows, and sample app architecture.

Component descriptions outlining responsibilities and interfaces for transport, codec, signing, and storage layers.

Acceptance Criteria

Architecture validated against requirements from Milestone 1.

Documented fallback strategies and clear dependency mapping.

Design supports wallets, dApps, and hydra-node without requiring custom forks.

Addresses scale, crash safety, and transport security.

Evidence of Completion

Feasibility Report and Architecture Blueprint published in the public repository (with diagrams and ADRs)

Delivery Month

2

Cost

20000

Progress

30 %

Milestone Title

Prototype Creation

Milestone Outputs

Flutter SDK Alpha including:

• Core client with typed messages, connection/reconnection logic, back-pressure controls, and optional history/snapshot handling.
• Transaction adapters for building/signing simple in-head payments.
• Reference wallet-bridge adapters for deeplink/webview signing flows.
• Minimal “micropayments” sample app demonstrating end-to-end functionality.

Testing Assets:

• Unit and integration tests covering connect, open/join, commit, payment, close, and error handling flows.

Acceptance Criteria

**Operational core features demonstrated: **open a Head, commit from two clients, send a payment, observe confirmations, and close.

Prototype integrates cleanly with hydra-node, wallets, and sample dApps.

Stable operation with no critical crashes; all tests reproducible in CI.

Evidence of Completion

Prototype documentation and usage guides in the repository.

CI passing badge.

Demo recording, test reports, and tagged alpha release.

Delivery Month

4

Cost

20000

Progress

80 %

Milestone Title

Release & Project Conclusion

Milestone Outputs

Final Project Report & Closure:

Full documentation from project initiation to public release, including key decisions, trade-offs, and lessons learned.

Performance review covering latency, throughput, reliability, and KPI outcomes.

Public Release:

Versioned packages published to Flutter’s pub.dev with semantic versioning.

Complete documentation site, reference implementations, and recorded walkthroughs/workshops.

Acceptance Criteria

Documentation is clear, complete, and actionable for external teams.

KPI targets met (e.g., successful POCs by at least two external teams).

SDK installable from public registry; sample apps run successfully against public hydra-node instances.

Evidence of Completion

Final report and slide deck committed to the repository.

Release tags and published packages on pub.dev.

Public docs URL and workshop recording linked in README.

Delivery Month

5

Cost

20000

Progress

100 %

[Final Pitch] Budget & Costs

Please provide a cost breakdown of the proposed work and resources

Milestone 1 – 20,000 ADA

Senior Cardano Developer – 12,000 ADA

Mobile Developer – 8,000 ADA

Milestone 2 – 20,000 ADA

Senior Cardano Developer – 12,000 ADA

Mobile Developer – 8,000 ADA

Milestone 3 – 20,000 ADA

Senior Cardano Developer – 12,000 ADA

Mobile Developer – 8,000 ADA

Milestone 4 – 20,000 ADA

Senior Cardano Developer – 12,000 ADA

Mobile Developer – 8,000 ADA

Total: 80,000

[Final Pitch] Value for Money

How does the cost of the project represent value for the Cardano ecosystem?

This project provides high value to the Cardano ecosystem by delivering a production-ready, open-source Flutter SDK for Hydra that will significantly reduce the barrier for mobile developers to adopt Hydra. The funding will directly support research, SDK architecture, implementation, testing, documentation, and open-source release, creating reusable infrastructure that benefits multiple projects beyond the initial scope.

We have structured the budget to cover only essential tasks, using in-house expertise and proven delivery processes to avoid unnecessary overhead. The SDK will be designed for longevity, modular, well-documented, and aligned with Hydra Family guidelines, ensuring that it can be reused, extended, and integrated into future mobile apps with minimal additional cost.

The impact extends beyond a single release:

• Developers save weeks of integration time thanks to ready-to-use APIs, examples, and wallet adapters.
• Cardano gains a standardized, reliable way for Flutter apps to use Hydra, increasing interoperability.
• Broader adoption of Hydra’s low-latency transactions will drive more on-chain activity, higher transaction volumes, and greater ecosystem utility.
• By focusing on reusable, open-source deliverables and shared developer standards, this project maximizes the return on ADA spent, generating long-term value well beyond the initial investment.

[Required Acknowledgements] Consent & Confirmation

Terms and Conditions:

Yes