release build white-screens on launch, dev client and simulator are both fine release-crash

Your order is right and the first step is the one people skip.

Reproduce locally with npx expo run:android --variant release. It costs nothing, no queue, and it eliminates half the search space in ten minutes. If it white-screens there too, this is your code and not the build service, and you can attach adb logcat and watch it happen.

When you read logcat, take the first fatal, not the last. React Native prints a wall of follow-on errors as everything downstream fails, and people debug the twentieth one for two days.

Second: environment. Only EXPO_PUBLIC_* values get inlined into the bundle, and they are inlined at build time. A key you set in a dashboard after the build does not exist in that binary. Something reading process.env.SOMETHING.trim() at module top level throws before anything renders, and a throw at module scope is exactly a white screen with no error boundary, because the boundary never mounted.

That second one is my guess for your symptom, given dev works.

Put crash reporting in with source maps uploaded from the build itself, not from your laptop afterwards. Once you can read a symbolicated stack from a release binary, this entire category of problem goes from a weekend to twenty minutes, permanently. It is the highest leverage thing on this list and it is the one people postpone.

Specific cause worth ruling out: something imported by shipped code that is only in devDependencies. Works everywhere in development, gets dropped by the production install on the build server, and the failure looks exactly like yours.

It is Hermes. Turn it off and use JSC, that fixes release-only issues like this.

Check that app.config.js is not reading something from process.env at config evaluation time that only exists on your machine. That produces a build whose configuration is subtly different from everyone else's and it is invisible in the diff because the file looks the same.