China is arguably the most cashless, mobile-first society on the planet. From buying street food to riding bullet trains, everything runs on high-speed digital rails.

Yet, for foreign software engineers, remote workers, and travelers, this hyper-digital landscape creates a formidable invisible wall:

Google Maps drifts into rivers due to China’s mandatory non-linear coordinate system.

Overseas credit cards get rejected by street taxi drivers and local payment terminals.

Western communication tools (WhatsApp, Slack, GitHub) get trapped behind the Great Firewall.

Over the past few months, I built China Travel Smart — an open, zero-login, static digital survival toolkit designed to solve these regional digital borders.

Here is the architectural breakdown, the coordinate transformation rabbit hole, and the engineering decisions behind the project.

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