Multiplatform Marketplace App Development

@Microlent

Hello, I am Dr. Rajesh Rolen, PhD in Computer Science & Engineering, with experience of over 20+ years in Android, App Development, Flutter, iOS Development, Mobile App Development, React Native, Payment Gateway Integration As a preferred freelancer in the top 1%, I have done 400+ projects here on freelancer.com, I have 4.9 ratings out of 5 on average, which showcases my quality of work and timely delivery. Key Highlights: - Free Hosting Support on the Cloud or any desired platform. - Free 3 months of post-delivery support to ensure that our client doesn’t face any challenges after the launch of the project. - Free Dedicated tester on projects to ensure quality delivery, so clients don’t need to act as a tester. - 10+ Years experience UI/UX team to ensure intuitive UI. Portfolio: https://www.freelancer.com/u/Microlent Please open the chat and send me a message, so we can have a more detailed discussion about the project to give you the project timeline and cost. Thank you for considering my services. I look forward to engaging in a productive conversation and understanding how I can be of assistance in bringing your project to life. Regards Rajesh Rolen

@ozbas

Dear Client, I am highly experienced in developing robust cross-platform mobile applications using Flutter and React Native, perfectly aligning with your requirement for a single codebase buy-and-sell app for iOS and Android. I understand your need for streamlined user flows. The WhatsApp chat button feature will be seamlessly incorporated to facilitate direct buyer-seller communication. The admin console will be lightweight yet functional, enabling you to suspend users and edit listings easily. I will provide full source code with comprehensive setup instructions, ready-to-test iOS and Android builds, and a basic web admin panel. Additionally, I will offer a concise hand-off session to guide you through publishing and maintenance. My approach emphasizes maintainability, lean architecture, and clear documentation. Please let me know if any feature details need clarification before development begins. Looking forward to collaborating. Best regards, Özgür

@Hammadhassan21

Howdy, A marketplace like this succeeds when buyers can find the right item, understand how they’ll receive it, and contact the seller without unnecessary steps. For a lean first version, I’d keep the focus on making listing, finding, and contacting sellers quick rather than adding unnecessary marketplace complexity. Flutter would be a practical choice for one codebase across iOS and Android, with authentication, listings, payments, and the lightweight admin panel kept as separate pieces. The pickup and post distinction is also worth building into the listing flow from the start, since it affects both the buyer’s checkout path and whether payment happens online or in person. The WhatsApp handoff can stay simple so buyers can move from the listing directly into a seller conversation without adding another complicated messaging system. I can show similar marketplace and mobile examples in chat if useful, along with how I’d structure the MVP so it stays easy to expand later. Do you already have a preferred payment gateway for the online checkout? Portfolio Link: https://www.freelancer.pk/u/Hammadhassan21 Best regards, Hammad Hassan

@starttechno

This marketplace app can be delivered as a lean Flutter application for iOS and Android, backed by Firebase for authentication, database, image storage, and secure listing data. I’ll implement quick Google sign-in and mobile OTP registration, with listings supporting new, pre-owned, and refurbished items, multiple photos, pricing, seller details, and either local pick-up or postal delivery. Buyers will have separate online checkout and cash-on-pick-up flows, plus a direct seller-chat button for last-minute questions. I’ll also build a lightweight web admin console where you can suspend users, review or edit listings, and remove inappropriate content. The project will include clear setup documentation, configured release builds for TestFlight and Android internal testing, and a concise hand-off walkthrough covering publishing and everyday maintenance. Payment integration will be isolated behind a simple service layer so a standard gateway can be changed later without rebuilding the marketplace. My relevant experience includes SyncWave, a cross-platform Flutter/React Native-style mobile product with Android TV support, as well as SwiftKhata, a production web, desktop, and mobile system. I have 10+ years’ experience, 249+ delivered projects, and a 4.9-star record. Should cash pick-up orders bypass online checkout completely, with payment marked manually by the buyer or seller? Muhammad Saad

@asifalimzd

Hi, I can build your buy-and-sell marketplace as a lean cross-platform Flutter app for both iOS and Android. I’ll cover Gmail/Google and mobile OTP authentication, product listings with images and pickup/post options, online or cash payments, and direct WhatsApp buyer-seller communication. I’ll also provide a simple web admin panel for managing users and listings, secure backend/API integration, release-ready builds, clean source code, and setup documentation. I’ll keep the architecture scalable while avoiding unnecessary complexity and can handle the deployment process for both app stores. Please send me a message so we can clarify the payment/delivery flow and get started.

@zainalitariq245

Hi i can show you my similar live published marketplace platforms, The main challenge is keeping the marketplace simple while making buying and selling reliable across two payment methods and two delivery options. I would build the core listing and checkout flow around clear pickup or postal choices, with quick Gmail or OTP onboarding and WhatsApp handoff for buyer and seller communication. The admin side would stay lightweight for managing users and listings. I have developed cross platform apps with Flutter, authentication, marketplaces, payment gateways, media uploads, admin panels, and API integrations. I would keep everything in one maintainable codebase and prepare the Android and iOS builds with clear deployment documentation. Business idea: You could later add seller ratings, order history, saved listings, and location based discovery without changing the basic marketplace flow. Should online payments be completed inside the app, or through a hosted checkout page?? PS: You’ll get competitive rates with the quality you deserve. After discussing your requirements ican suggest the best scalable approach and provide an estimated timeline and cost. My portfolios, https://www.freelancer.pk/u/zainalitariq245 Looking forward to discussing your project further. Best Regards, Zain A.

@kabirchy

Hi there, I can build a dependable buy-and-sell marketplace app for iOS and Android from a shared codebase using Flutter or React Native, depending on your preferred long-term maintenance path. The app will support user profiles, item listings for new, pre-owned, and refurbished products, category filtering, search, saved listings, and direct messaging between buyers and sellers. For fulfillment, I will implement two clear options: local pick-up with address or geolocation support, and postal delivery with shipping status tracking, seller shipping notes, and buyer confirmation. I will also integrate a secure payment flow where applicable, with order states for pending, shipped, delivered, and completed, plus basic admin moderation for listing approval and dispute review. A lightweight chatbot can guide users through listing creation, deal selection, payment questions, and common support topics. I will set up a clean database schema for users, listings, conversations, orders, and reviews, and include push notifications for messages, order updates, and new nearby matches. The result will be a simple, trustworthy marketplace that works smoothly on both platforms and is ready for future scaling. Best Regards, Khorshed Alam, RS Software

@pinkeegupta

Hi I will be able to help you. Please message me so that we will have detail technical discussion. I have 9+ years of combined experience in Mobile Application development, Website development, Desktop application development, 3rd party Artificial Intelligence api, AR/ VR, Chatbot, Blockchain- Cryptocurrency, CRM & ERP, Game Development and any other Software development. Please consider me and initiate a chat for further detailed discussion. Regards, Anju

@Eliteinno

Hello, A lean marketplace can work well with a single Flutter or React Native codebase, but the important part is keeping authentication, listings, payments, image storage, moderation, and buyer-seller communication consistent across both platforms. The admin panel should also control the same marketplace data rather than becoming a separate management system. I would build the first version around a simple listing lifecycle, Google/OTP authentication, pickup versus postal options, WhatsApp handoff, and a payment abstraction that leaves room for the chosen gateway. Mobile image handling and offline/error states also need attention because sellers will commonly create listings from variable network conditions. For the first milestone, would you prefer online payments included immediately, or should the MVP launch with cash/WhatsApp transactions first? Have a nice day

@temoberishvili

Hey there! I see you're looking to create a reliable buy-and-sell app for both iOS and Android. Your goal to simplify the marketplace experience is something I’m excited about. With over 10 years of experience in mobile app development, I’m well-versed in React Native and Flutter, ensuring a smooth user experience. I've tackled payment gateway integration and database management, so I can help bring your vision to life effectively. Looking forward to the possibility of working together!

@doomshellsl

Hi, We can build your lean buy-and-sell marketplace app from scratch for both iOS and Android using Flutter or React Native, with a single maintainable codebase. We can deliver: • Gmail login and mobile OTP authentication • Seller listings with photos, pricing and item condition • Pickup/postal delivery options • Online payment gateway + cash payment flow • Buyer-seller WhatsApp integration • Backend, database and secure APIs • Web-based admin panel for users and listings • Responsive, user-friendly UI/UX • iOS & Android release builds for testing and store submission • Complete source code, documentation and handover We’ll keep the architecture lean and scalable while ensuring the core marketplace flows are reliable and easy to maintain. We can also guide you through app-store publishing and day-to-day administration. Our team has experience developing mobile applications, marketplaces, payment integrations, backend systems and admin dashboards. We’re ready to discuss your requirements and start the development from scratch.

@melikatfz

Hello, Is using React Native your preferred choice for this build? Do you already have a preferred payment gateway in mind for online checkout? Excited about your buy-and-sell app! I'll focus on a seamless user experience with quick sign-ins and a clean catalog for listings. Managing cross-platform challenges, like maintaining consistent performance on both iOS and Android, is key. I plan to ensure this with a single codebase approach. I'll send previous examples in chat. Let's dive into details over a brief chat or call. Happy to jump on a quick message anytime!

@SBITServices

Hi, I have 5+ years of experience in Flutter. I will design and develop a fully functional Flutter mobile application for your business. The app will be cross-platform, responsive, and optimized for both Android and iOS. I will ensure smooth navigation, clean UI, and reliable performance. My Skills Include: a) Flutter Development – Expertise in building cross-platform mobile apps with responsive UI. b) State Management – Experienced in Provider, Riverpod, and Bloc for scalable apps. c) Backend Integration – Skilled in connecting apps with REST APIs, Firebase, and third-party services. d) Database Handling – Proficient in Firebase Firestore, MySQL, and SQLite. e) Deployment & Support – Experienced with publishing apps on Google Play Store and Apple App Store. Lets connect in chat so that We discuss further. With Regards, Sai

@mehboobkatiyar

I’d build this as a single Flutter codebase for iOS and Android, with Gmail login plus phone OTP, a simple seller listing flow, image uploads, condition tags, pickup/post options, and buyer filtering. For payments, I’d keep online checkout behind a clean payment-service layer so the gateway can be changed later without touching the marketplace logic. Cash-on-pickup would remain a separate order path. The WhatsApp button can open a prefilled buyer-to-seller conversation without building an unnecessary in-app chat system. I’d also include a lightweight web admin panel for user suspension, listing edits/removal, and basic order visibility, then prepare TestFlight and Play Console builds with setup documentation and handover. One point to confirm before development: for postal orders, do you want delivery tracking inside the app or only seller-managed shipping?

@BarryCrouch

Keeping a multiplatform marketplace lean and easy to maintain means avoiding heavy custom server setups and using a unified backend like Supabase/Firebase for authentication, real-time listing feeds, and image hosting. I will deliver the complete cross-platform mobile app and lightweight web admin panel—wiring Google sign-in, instant WhatsApp chat handshakes, flexible checkout/cash options, and preparing signed builds for TestFlight and Android internal testing. I provide a written progress update every three days against defined milestones. For the mobile OTP verification flow, do you already have a Firebase or Twilio project configured, or should I set that up from scratch? Would you like to review a quick technical roadmap for the app and admin console today before we begin building?

@A2Design

Hello, A2 Design can help build your lean buy-and-sell marketplace with a single React Native codebase for iOS and Android, covering Gmail/OTP registration, seller listings with photos and delivery options, online or cash payment flows, WhatsApp chat handoff, and a lightweight admin panel for user/listing moderation. We’ve built marketplace-style platforms for startups, including MadPaws, an on-demand services marketplace with search, booking, profiles, filtering, and payments: madpaws.com.au. We also developed Get Blys, a service booking platform with secure payments and scheduling flows: getblys.com.au. These projects align well with your need for a reliable, user-friendly mobile marketplace and simple operational tools. We can deliver the source code, setup documentation, TestFlight/internal testing builds, admin console, and a focused hand-off session for publishing and maintenance. Let’s connect to clarify the payment gateway, OTP provider, and listing rules, then we can outline the build plan and timeline.

@toriquldev123

Hello There! I’m Md Toriqul Islam, an experienced mobile/full-stack developer specializing in Flutter, Firebase, authentication, payment integration, and cross-platform app development. I’m excited to partner with you and can start immediately. I understand you need a lean buy-and-sell marketplace for iOS and Android with Gmail/mobile OTP login, product listings, pickup/post options, online or cash payments, WhatsApp buyer-seller communication, and a simple admin panel. I am skilled in Flutter, Firebase, OTP/social authentication, REST APIs, payment gateways, WhatsApp integration, databases, admin panels, and App Store/Play Store deployment. I have a few questions: 1) Which payment gateway and country/market should the online checkout support? 2) Should sellers and buyers have separate profiles, or can each user perform both roles? 3) Do you already have the app branding/UI design, or should I create a simple modern interface? I’m ready to build this with a single maintainable codebase and provide complete source code, release builds, documentation, and hand-off support. Looking forward to hearing from you. Best regards, Md Toriqul Islam

@msaqibimran

Hi, I see you're looking to create a simple yet effective buy-and-sell app that facilitates both local pick-up and postal delivery options. This dual focus on ease of use in registration and a streamlined catalog for listing items is key to engaging users right from the start. My approach would involve clarifying the app's architecture, developing the core features for both platforms, and ensuring a solid testing phase to deliver a stable and user-friendly experience before launch. Given the emphasis on a single codebase, I recommend leveraging Flutter for its efficiency and performance across iOS and Android. To tailor this project more closely to your vision, do you already have any wireframes or user flows in mind? Understanding your initial design intentions would help in shaping the project effectively. I prioritize clean architecture and reliable performance, ensuring that the app is robust and ready for real users right from day one. This means focusing on seamless integration of features like quick registration, payment processing, and the chat function with WhatsApp. I would appreciate the opportunity to discuss this further so we can accurately scope the timeline and pricing for your project. Regards, Mohammad

@technologiesit

As a seasoned Full Stack Developer and a Flutter Expert, I am highly equipped to lead your Multiplatform Marketplace App development project. With a massive experience spanning over 8 years and successfully delivering more than 200 projects, I bring to your table proven expertise in delivering fast, scalable, and result-oriented digital solutions that exactly align with your needs. My distinct skill set in offering comprehensive web development using Flutter (both Android & iOS) is just what you need for your cross-platform requirement. Additionally, my exposure in building clean, secure, and scalable code perfectly compliments your emphasis on a single codebase, keeping your venture lean whilst ensuring optimal operational efficacy. If chosen for the job, I will not only deliver the desired full source code, iOS and Android release builds but also a basic web-based admin panel facilitating seamless control over user management and listing editing. Post-delivery, I promise to walk you through the entire publishing process as well as lend an unwavering long-term support; meeting all of your votre business growth needs. Let's connect today to create a remarkable market space that exceeds your vision while driving real results!