123safe67: A Short, Safer Way to Share Files on Android

Overview

I use 123safe67 as a tiny, memorable playbook for cross‑app sharing on Android. It isn’t a library just habits that keep links, files, and hand‑offs private and predictable.

What 123safe67 Means

• 1 intent: Keep a single, clear ACTION_VIEW or ACTION_SEND path per share
• 2 grants: Only grant read/write when needed, and revoke promptly
• 3 checks: Validate MIME type, file size, and URI scheme before opening
• safe by default: No raw paths, sanitize inputs, prevent traversal
• 6 fallbacks: Handle no app found, cache miss, permission loss, type mismatch, oversized files, and offline
• 7 user safeguards: Clear prompts, cancel path, no surprises, visible types, retry tips, privacy notes, easy feedback

Why It Matters

• Cuts the risk of leaking private files or directories
• Keeps behavior consistent across Android versions and OEM skins
• Gives users, testers, and reviewers a predictable experience

Core Workflow with 123safe67

1. Obtain a content:// URI from FileProvider or another app’s ContentProvider.
2. Resolve MIME via ContentResolver#getType(uri) and confirm expectations.
3. Start an intent with setDataAndType(uri, mime) and add Intent.FLAG_GRANT_READ_URI_PERMISSION.
4. For edits, request write access and verify support.
5. Catch FileNotFoundException and SecurityException; show friendly errors and retry paths.
6. Revoke any temporary grants after completion.

Designing for Privacy and Safety

• Prefer content URIs over file paths for app‑to‑app flows
• Scope access narrowly and time‑box it
• Sanitize filenames; verify type/size server‑side when uploading
• Avoid logging full URIs or sensitive paths
• Treat caches as ephemeral; don’t rely on permanence

Developer Tips

• Declare androidx.core.content.FileProvider for common cases
• Map only required directories with <paths>
• Use consistent authorities (e.g., com.example.app.fileprovider)
• Prefer ACTION_OPEN_DOCUMENT for persistent, user‑granted access
• Use takePersistableUriPermission sparingly and document why

User Tips

• Open content:// links with apps that support the file type (they aren’t web URLs)
• If a link fails, try another app or re‑share from the source
• Clear cache if a cached item vanishes or errors
• Don’t post device‑local URIs publicly—they won’t work for others

Testing Checklist (123safe67)

• Verify MIME and size before launch
• Simulate no matching app
• Reboot to confirm persisted grants
• Toggle network for upload flows
• Test multiple Android versions and vendors
• Purge cache to validate error handling
• Review logs for privacy hygiene

FAQ

• What is 123safe67? A practical checklist and mindset for safer cross‑app sharing.
• Is it a library? No—just guidance you can apply anywhere.
• Android‑only? Principles apply broadly, examples focus on Android.
• Works for images and PDFs? Yes—any content type across apps.
• How does it protect privacy? By minimizing/revoking access, validating types, and avoiding raw file paths.

Conclusion

With 123safe67, I keep sharing flows resilient, private, and predictable. Adopt the habits, adapt them to your app, and you’ll reduce errors while earning user trust.