sha256sum — Hash & Compare

Ever copied a folder to a USB drive, a new phone, or a cloud backup — and later wondered whether every single file made it across safely? sha256sum gives you a definitive answer.

The app scans your folders and creates a "fingerprint" for every file — a short code that changes the moment even one byte is different. You can compare two folders side by side (a backup and the original, for example) and the app will tell you exactly which files are only on one side, and which ones differ.

No accounts, no cloud, no tracking. Everything stays on your device and the storage you pick.

Hash tab
Pick a source folder and an output file. Tap "Compute hashes". The app walks the entire folder tree and writes one fingerprint line per file in the standard `sha256sum` format — compatible with Linux, macOS, and Windows tools.

Compare tab
Pick two folders, two existing `.sha256` manifest files, or mix and match. Differences appear live in a tree view as the scan runs. Green means only on the left, orange means only on the right, red means the file exists on both sides but the content differs.

Who is this for?
- Photographers and videographers verifying archive transfers
- Anyone doing backups who wants byte-perfect confirmation
- IT professionals auditing file sets
- Developers and sysadmins already familiar with `sha256sum` on the command line

Key features
- Generates standard `sha256sum`-format manifest files (compatible with all major platforms)
- Folder vs. folder, folder vs. manifest, or manifest vs. manifest comparison
- Live results — differences appear as files are scanned, no waiting
- Supports USB drives, SD cards, and any Android-accessible storage via the Storage Access Framework
- Pause and resume long operations; runs as a foreground service with a persistent notification
- No internet permission required