Since releases ship an `.apk.sha256` file, every in-app update checks
the downloaded APK against it. The check read the 40 MB file in base64
chunks and hashed it in JS, which took longer than the download, and it
reset the progress bar to 0 under the "Downloading" label, so the update
looked like it downloaded twice, the second time slowly.
The file is now read and hashed natively through expo-crypto (the JS
hasher remains as a fallback), and the bar stays full under a
"Verifying…" label while the check runs.
Linus Rath
23af324d79