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I’m building an Android-only e-commerce app and need a clean, well-documented backend API to power it. The immediate scope centres on two pillars: secure user authentication and a fully working payment gateway. For authentication I want a modern, token-based flow with encrypted password storage, password reset and token refresh endpoints. OAuth2 or JWT is fine as long as the implementation follows OWASP recommendations and is easy to consume from an Android client (Retrofit will be used on the app side). On payments, the API must connect to a mainstream gateway—Stripe, PayPal or a similar provider—run in sandbox first, then be production-ready. Endpoints should let the app create an order, start a transaction, receive gateway callbacks/webhooks and return a clear success or failure payload. The product catalogue will be handled later, so focus your energy on these two modules and make the code modular enough for future expansion. Deliverables • REST endpoints for sign-up, login, logout and token refresh • Payment processing endpoints wired to the chosen gateway, fully tested with sandbox credentials • Environment configuration files plus a simple deployment script (Docker or similar) • Postman (or Swagger) collection and concise Markdown documentation covering auth flows, payment sequence and error codes Acceptance criteria • All endpoints respond with standardised JSON and appropriate HTTP status codes • Auth flow passes basic penetration tests; tokens cannot be forged or reused after logout • A sandbox payment completes with test credentials and returns a verified callback Feel free to use Node.js, Django, Laravel or another mainstream framework you’re comfortable with; just keep the code neat, unit-tested and ready to drop onto AWS or Heroku.
Project ID: 40619373
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133 freelancers are bidding on average $220 USD for this job

Hello, As a team leader at A4Logic with years of experience in mobile app development and a specialty in Android, I can confidently say that we are the right fit for your project. Our portfolio showcases numerous successful projects similar to yours, where we've built robust backend APIs that power e-commerce apps. One of the core competencies of A4Logic is developing well-secured authentication systems, which we implement using modern approaches such as JWT or OAuth2. Furthermore, we take the security of your user's data very seriously, using encrypted password storage to protect personal information. To ensure scalability and maintainability, we always write code with future expansion in mind - making it perfect for integrating rest of the product catalogue later on. On top of that, having an extensive background in database applications and payment gateway integrations, I'm confident in our ability to connect your app to leading payment gateways such as Stripe or Paypal securely and seamlessly. Having delivered almost 500 projects with 97% completion rate, our strength lies not just in meeting requirements but in exceeding expectations. Let us worry about the technicalities while you focus on growing your e-commerce business. Choose A4Logic for this project and expect a meticulously built API with thorough documentation and long-term support Thanks!
$250 USD in 5 days
8.6
8.6

Hi, You’re not just asking for an API, you need the secure backbone that keeps Android payments trustworthy before the catalogue even exists. I can build a clean backend with token-based auth, password reset, refresh flow, and a modular payment layer for Stripe or PayPal, with OWASP-minded handling and standardized JSON responses. I work comfortably with PHP/Laravel, MySQL, REST APIs, webhooks, and deployment-ready setups, so I can structure this for easy Android consumption via Retrofit and future expansion. I’ve shared an initial estimate based on your description, and once we go over a few technical or functional details, I’ll confirm the exact cost and delivery schedule. I’ll also include sandbox testing, Postman/Swagger docs, and a simple Docker-based deployment path so the API is easy to verify and hand off. Which backend framework and payment gateway do you want me to prioritize first for the initial implementation? Looking forward to your reply so we can finalize the exact plan. Best regards, Asad
$75 USD in 3 days
8.2
8.2

Hi, I checked your "Android E-Commerce API Development" project and it looks like understanding the existing workflow will be important before making any changes. I've worked on similar PHP projects involving php, java, mobile app development, android, node.js, restful, payment gateway integration, api development and prefer delivering work in small milestones so everything stays easy to review and adjust if needed. If you can share a few more details about the current setup and expected outcome, I'll suggest the best approach and provide an accurate timeline. ⭐ 5.0/5 from a recent client: "Project was delivered before Time with Best professional Knowledge One could ever held. Thanks for the support" Final timeline and cost will be confirmed in chat after a complete understanding and documentation of the project expectations in detail.
$150 USD in 3 days
8.0
8.0

Hi sir, I read your project description .I can do your project & able to run successfully. I have 12+ years experience for website & mobile application development also done over 1000+ project by a good team members . It will be very much pleasure for me, if you give me the opportunity to do your job for minimum cost. Thanks for your consideration . Thanks with Regards Prosanto
$140 USD in 7 days
8.0
8.0

We build clean, well-documented REST APIs for Android e-commerce apps — authentication, payments, product catalog, and order management are standard deliverables for us. For your backend: • Auth: JWT-based login/register, bcrypt password hashing, refresh token rotation, email-based password reset • Payment gateway: Stripe or PayPal — charge, refund, webhook for order confirmation, receipt email • Product endpoints: listing, search/filter, product detail, stock check • Cart + Orders: add/remove items, checkout, order history, status updates • Admin endpoints: basic product/order management for your CMS • Documentation: Postman collection + README so your Android dev can integrate immediately • Stack: Node.js + Express + MySQL (or Laravel if you prefer PHP) Deliverable in 10 days. Which payment gateway do you want — Stripe, PayPal, or a specific provider? And do you already have the Android app in progress or starting that in parallel?
$200 USD in 7 days
8.2
8.2

I'm Faisal, a seasoned mobile app developer with an immense expertise in Android and Web Development. Over the last six years, I have crafted successful digital solutions that are not only innovative but also highly user-centric. My adeptness in working with diverse platforms will undoubtedly be an asset in building your Android E-Commerce API. On the specifics of your project, I have a deep understanding of secure user authentication flows and payment gateways, which align perfectly with your immediate requirements. With previous experience crafting complex token-based authentication systems and implementing various payment gateway APIs, I can assure you of a clean, well-documented backend API that's in line with OWASP recommendations. My extensive background includes leveraging OAuth2 or JWT for secure and efficient services which should seamlessly integrate with Retrofit on the app side.
$300 USD in 7 days
7.2
7.2

Hi, I can build a secure, production-ready backend API for your Android e-commerce app with JWT authentication, password reset, token refresh, and payment gateway integration. I have experience with Node.js, Python (FastAPI), Django, REST APIs, Stripe/PayPal integrations, Docker, and AWS deployments, and I'll deliver clean, modular, well-documented code with Swagger/Postman support and comprehensive testing. Thanks Anshuman
$200 USD in 7 days
6.4
6.4

As an experienced and highly skilled Full-Stack developer with a passion for clean architecture and maintainable code, I am confident that I am the ideal choice for your Android E-Commerce API Development project. My expertise ranges from Web Development in React and PHP to Mobile Apps in React Native and Flutter, including proficiency in Node.js and Laravel which align perfectly with the technologies you've mentioned. Having successfully built and integrated REST APIs for well-known providers such as Stripe, PayPal, Twilio among others, I am undoubtedly capable of delivering the top-notch solutions your project is seeking. My knowledge in secure user authentication using OAuth2 and JWT combined with my commitment to adhering to OWASP recommendations will guarantee a robust token-based flow for your app. Additionally, my familiarity with Retrofit means that I can seamlessly optimize those endpoints to suit your needs.
$30 USD in 3 days
7.1
7.1

I can develop a secure, modular backend API with JWT/OAuth authentication, encrypted password handling, token refresh, and a fully integrated Stripe or PayPal payment gateway, complete with webhooks, Docker deployment, and comprehensive Swagger/Postman documentation. The API will be production-ready, follow OWASP best practices, and be optimized for seamless Android integration and future expansion. Best Regards, Muhammad
$30 USD in 1 day
6.3
6.3

Hello Dear, I’m Md. Toriqul Islam, and I’m excited to partner with you. I can dive into your project immediately. I have rich experience in backend API development, Laravel, Node.js, Django, JWT authentication, and payment gateway integration. I understand you need a secure, modular backend API for your Android eCommerce application with token based authentication, password management, and production ready payment processing. I’ve developed scalable REST APIs with OWASP compliant security, standardized JSON responses, Docker deployment, and comprehensive API documentation. I am skilled in Laravel, Node.js, Django, JWT, OAuth2, Stripe, PayPal, Docker, Swagger, and REST APIs. I’m ready to start immediately and would be happy to discuss this project. Looking forward to hearing from you. Best regards, Md. Toriqul Islam
$70 USD in 3 days
6.2
6.2

Hello, this is a fairly clean backend scope, and the part that matters is getting auth and payment state transitions correct so the Android app has predictable behavior through Retrofit. The real engineering risk is not the endpoints themselves; it is token revocation and webhook-driven payment finalization, where race conditions and replay handling usually create production issues. I've built several production API systems like this with secure auth, documented REST contracts, and AWS-ready deployment patterns. The closest match in my background is Dent-Cloud for secure Node.js API design, auth, Swagger documentation, and cloud deployment. Enterprise ProxyTool Client App is also relevant from a systems perspective because it required strict separation of control flows, security boundaries, and backend service contracts. I usually structure this as separate auth, order, and payment modules, with payment status driven by verified callbacks rather than client-side assumptions. That keeps the API extensible when catalog, inventory, and refunds are added later. I would also put attention on refresh-token rotation, logout invalidation, idempotent order creation, webhook signature verification, and standardized error payloads. If useful, I can sketch the endpoint contract and payment-state flow first so the implementation stays clean and testable. Clifton
$200 USD in 7 days
5.9
5.9

Hello, I can build a secure, production-ready backend API for your Android e-commerce application with a strong focus on authentication and payment processing. I'll implement JWT/OAuth2 authentication following OWASP best practices, including sign-up, login, logout, password reset, and token refresh. I'll integrate Stripe, PayPal, or your preferred payment gateway with complete sandbox testing, webhook handling, and production-ready configuration. The API will provide standardized JSON responses, proper HTTP status codes, and clean, modular architecture for future expansion. I'll also deliver Docker deployment, Postman/Swagger documentation, unit tests, and concise Markdown documentation. My experience includes Node.js, Laravel, Django, REST APIs, AWS deployment, and secure payment integrations. I write clean, scalable, and well-documented code with regular progress updates. I'm ready to start immediately and ensure the backend is reliable, secure, and easy for your Android team to integrate. Best Regards Jitendra Sharma
$200 USD in 20 days
5.5
5.5

Hi, I hope you're doing well. I have carefully reviewed your project, Android E-Commerce API Development , and I'm confident I can deliver a high quality solution tailored to your requirements. I'm a Full Stack Developer with 4+ years of experience building websites, SaaS platforms, AI powered applications, automation tools, web scrapers, lead generation systems, and custom software. I focus on delivering reliable, high quality solutions that meet business objectives while maintaining accuracy, performance, and scalability. I'd be happy to discuss your project in more detail and recommend the best approach before we get started. I look forward to working with you. Best regards, Arslan Shahid Full Stack Developer | Technical Fixes | AI Automation | Lead Generation & Extraction Expert | Websites Dev
$30 USD in 7 days
5.7
5.7

Hi, I have extensive experience building secure REST APIs using Node.js, Django, and Laravel, with JWT/OAuth2 authentication, Stripe/PayPal integrations, webhooks, Docker deployment, and Swagger/Postman documentation. I can deliver a modular, production-ready backend with secure authentication, sandbox-tested payment processing, standardized JSON APIs, and clean documentation that's ready to integrate with your Android app. Regards, Shakila Naz
$300 USD in 7 days
5.5
5.5

✋ Hi There!!! ✋ The Goal of the project:- BUILD A SECURE, MODULAR AND WELL-DOCUMENTED REST API FOR ANDROID E-COMMERCE AUTHENTICATION AND PAYMENT PROCESSING. 1. Implement secure JWT or OAuth2 authentication with encrypted passwords. 2. Add signup, login, logout, password reset and token refresh endpoints. 3. Integrate Stripe, PayPal or similar gateway with sandbox testing and webhooks. 4. Provide standardized JSON responses, validation, error handling and unit tests. 5. Deliver Docker deployment setup, Postman or Swagger documentation and AWS-ready code. <-- Questions --> 1. Which payment gateway do you prefer for the initial implementation? 2. Do you already have an AWS or Heroku deployment environment? Similar backend API projects have been completed using Node.js, Laravel and REST APIs with secure authentication, payment gateways, webhooks, testing and complete API documentation. Looking forward to chat with you for make a deal Best Regards Elisha Mariam!
$1,400 USD in 10 days
5.1
5.1

Hi there, Auth and payments are the two modules where shortcuts cost the most later, so scoping them first is the right call. My approach: Node.js + Express with JWT access/refresh token pairs, bcrypt password hashing, and server-side token revocation so logout genuinely invalidates — that's the part most implementations get wrong and it's explicitly in your acceptance criteria. Rate limiting and OWASP-aligned validation throughout. For payments, Stripe in sandbox first, with webhook signature verification so callbacks can't be spoofed. Clean separation between order creation, transaction initiation and callback handling, returning standardised JSON with proper status codes. Deliverables: all auth and payment endpoints, env config, Dockerfile and deployment script, Swagger/Postman collection, and Markdown docs covering flows and error codes. Structured modularly so the catalogue drops in later without refactoring. Retrofit-friendly response shapes throughout. 130+ reviews. Available immediately. Best regards, Vishruth
$60 USD in 2 days
5.3
5.3

Hi, I understand the priority is building a secure, scalable backend API with rock-solid authentication and payment processing that your Android app can integrate with effortlessly. I have experience developing REST APIs with JWT authentication, secure password handling, Stripe/PayPal integrations, webhooks, and clean documentation, ensuring the backend is production-ready and easy to extend as new e-commerce features are added. Which backend framework do you prefer for this project—Node.js, Laravel, or Django—or would you like me to recommend the best option? Looking forward for positive response in the chatbox. Best Regards, Hassan H
$200 USD in 7 days
5.4
5.4

With me, Mahad Sheikh, at the helm of your Android E-Commerce API Development project, you're guaranteed an API that smoothly handles secure user authentication and seamless payment processing. Throughout my career, I've honed my skills in areas critical to your project's scope: password encryption in line with OWASP recommendations, token-based flows like OAuth2 and JWT, and utilizing mainstream payment gateways such as Stripe or PayPal. I'm not only a technology expert but also a business strategist. As part of our work relationship, I'll ensure that the backend solution I deliver aligns seamlessly with your business goals and remains flexible enough for future innovations to be incorporated easily. This modular approach will save you time and resources in the long run. Finally, my experience spans various industries from startups to multi-national enterprises, making me adaptable to the ever-evolving e-commerce landscape. So let's build secure, elegant functionality that doesn't just meet your immediate needs but supports lasting growth as your company scales.
$200 USD in 6 days
5.4
5.4

Hi, I can develop a secure and well-documented backend API for your Android e-commerce app, focusing on user authentication and payment processing. To ensure I meet your requirements effectively, could you confirm whether you prefer a specific tech stack like Node.js, Django, or Laravel, or would you like my recommendation? Additionally, please clarify if you have any existing designs or documentation for the app, or if this is the initial development phase. I will create REST endpoints for user sign-up, login, logout, and token refresh, implementing a modern token-based authentication flow that adheres to OWASP recommendations. For payment processing, I will integrate with a mainstream gateway such as Stripe or PayPal, ensuring the API can create orders, handle transactions, and manage callbacks with clear success or failure responses. The code will be modular to allow for future expansion, and I will provide environment configuration files along with a deployment script. Documentation will include a Postman or Swagger collection detailing the auth flows, payment sequences, and error codes. Let’s connect for a quick discussion to finalize the scope, timeline, and pricing. Regards, Mohammad
$170 USD in 10 days
5.4
5.4

I can develop a backend API for your Android eCommerce app with token-based authentication, encrypted password management, password reset and OAuth2 implementation. I'll also integrate a payment gateway with complete order, transaction, webhook and response handling. Let's connect so we can discuss more about it. Regards, Shawana
$300 USD in 6 days
4.9
4.9

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