I’m building a mobile marketplace where buyers can post the jobs they need done and sellers can submit bids in real time. The product must launch simultaneously on iOS and Android, so a cross-platform stack such as Flutter or React Native is ideal, but I’m open to other solid solutions that keep a single code-base. Core experience I need you to deliver: • Secure sign-up and login (email, social, or phone). • A smooth flow for buyers to create a work request, attach photos or brief files, and publish it publicly. • A live bidding interface where sellers can place, edit, and withdraw offers until a buyer accepts. • In-app messaging so both sides can negotiate or clarify details without leaving the platform. • PayPal integration for deposits, milestone releases, and final payments, handled through PayPal’s native SDKs to stay within their compliance rules. I’ll supply wireframes and basic brand assets; you’ll turn them into a polished, deployable app, set up the backend (Firebase or your recommended alternative), and walk me through TestFlight and Play Console submissions. Clean, well-commented code and a brief hand-over document complete the job.