Custom or White-Label Messaging App (20–200 Users) — WhatsApp/Discord Style

We are looking for a developer to build or customise a cost-effective, private enterprise communication platform for a small company (20 to 200 users total). It does not need to be an exact clone of WhatsApp—a... (Budget: £20 - £250 GBP, Jobs: API Development, App Development, Cloud Computing, Database Management, Frontend Development, Mobile App Development, Security, User Interface / IA, Web Application, Web Development)