Title: Develop a Real-Time Mobile App for Monitoring New Listings on adswebsite

Title: Develop a Real-Time Mobile App for Monitoring New Marktplaats Listings Project Overview I am looking for an experienced developer or development team to build a mobile application (Android and/or iOS) that monitors Marktplaats.nl in real time and instantly notifies me when a new listing matching my keywords is published. The primary goal of this project is speed. Marktplaats already offers standard notifications, but I want a significantly faster solution that provides the earliest possible notification after a listing goes live. Required Features * Monitor Marktplaats.nl continuously for newly published listings. * Allow me to define one or more keywords and search criteria. * Send instant push notifications when a matching listing appears. * Display the listing details immediately within the app. * Allow one-tap contact with the seller. * One-tap phone calling when a phone number is available. * One-tap emailing of the seller. * Automatic insertion of predefined email templates so I can respond immediately. Performance Requirements * The system must be optimized for the lowest possible latency. * Notifications should arrive as close to real time as technically possible. * Speed is more important than visual design. * The objective is to receive notifications before or faster than standard Marktplaats notifications whenever possible. Technical Investigation Required Before development begins, I would like the developer to investigate how Marktplaats publishes and updates new listings. Specifically: * Determine whether Marktplaats uses internal APIs, WebSockets, server-sent events, or other real-time mechanisms. * Identify the fastest technically feasible method for detecting new listings. * Compare this approach against traditional page-refresh or scraping methods. * Recommend the architecture that provides the lowest possible delay. I am not looking for a simple scraper that refreshes pages every few seconds. I am looking for the fastest and most efficient monitoring solution that is technically possible. Developer Requirements * Experience with mobile app development (Android/iOS). * Experience with real-time monitoring systems. * Experience with web scraping and/or API integration. * Experience with push notification systems. * Strong understanding of performance optimization and low-latency systems. When Applying Please include: * Examples of similar projects you have completed. * Your proposed technical approach. * Whether you believe it is possible to outperform standard Marktplaats notifications. * Estimated development timeline. * Estimated total cost. I am looking for a developer who understands that speed is the primary objective of this project.