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Not everything is as simple as you think. There will be a lot of backend, because not only do you need to communicate, but you also need to store a lot of data, work with the database and much more. Most of these applications are 50-60% backend work. You can order video chat apps development service https://owlab.group/our-blog/post/how-to-create-a-video-chat-app-features-techstack-and-development-cost from this company. They have a lot of high-level specialists.