Heavy Transport Escort App

I need a single code-base application that lets companies who move oversize loads find and book escort drivers quickly. The priority is a smooth, real-time chat that connects the load owner with available escorts the moment a request is posted. The conversation thread should stay synced across iOS, Android, and a responsive web portal, so whichever device people pick up, the same history, files, and read receipts appear instantly.

Alongside chat, a lightweight map is required. It only has to display origin, destination, and the suggested route; live traffic layers or GPS tracking can wait for a later phase. Think of it as a visual aid inside the chat window that both sides can reference while they negotiate.

Key screens I expect:

• Escort marketplace where drivers list their availability and vehicle specs
• Chat window with file/image share and push notifications
• Map pane showing basic routes between entered points

You are free to choose the tech stack, but please outline why it is the best fit for a shared code base and how you will maintain feature parity across iOS, Android, and Web. Once the first build is ready I will test on all three platforms, so include simple installation instructions or hosted links for each.

Acceptance will be based on:

• Seamless chat performance (no lost messages, consistent timestamps)
• Accurate map rendering of basic routes on every platform
• A working escort listing flow that ends in a confirmed booking record

If you have shipped a cross-platform chat app before, show me an example and tell me what framework you used.