School-Parent Chat App Development

I need a cross-platform (iOS and Android) real-time messaging app that offers WhatsApp-style usability but is purpose-built for school–parent communication, taking inspiration from moya.app. Key functions I expect: • Flexible group structure – create grade-specific channels, a whole-school broadcast list, an educators-only room, plus a single consolidated inbox for the School Governing Body. • Notifications centre – schools can push urgent notices, while an adjacent, clearly marked feed lets businesses buy ad space and publish sponsored posts. • Advertiser mini-sites – each paying company should be able to spin up a simple, templated landing page inside the app that opens in-app, keeping parents engaged. • Core chat features – text, voice notes, images, read receipts, file sharing, and robust admin controls, all secured to current best practices. Build it once, ship it on both iOS and Android; React Native or Flutter is acceptable as long as performance feels native. Timeline is tight—I’m aiming for a usable MVP as soon as possible, complete with source code and concise technical documentation. When you reply, please share links to comparable chat products you’ve delivered and outline the tech stack you would choose.