Backup, migration, offline use and FAQ

Do I need to register or sign in?

No. Core features do not require email, phone, Apple ID, Google sign-in or an App membership account.

Can I use it offline?

Yes. Content, reference audio, placement, answers, spaced review and progress stats run on device. Network may only be needed when the user actively uses an OS file provider to share or pick a file.

How do I back up progress?

Open Settings & Backup → Export encrypted backup, set a passphrase of at least 8 characters, then save via the system share sheet to iCloud Drive, Google Drive, NAS or local storage.

I forgot the backup passphrase

It cannot be recovered. The passphrase is not uploaded or stored by NaviaWorks. Keep the current device data and create a new backup with a new passphrase; old backups still need the original passphrase.

How do I move from Android to iPhone/iPad?

1. Export an encrypted .eab on Android.
2. Store the file somewhere both devices can open.
3. On iPhone/iPad open Settings & Backup → Preview and restore backup.
4. Enter the passphrase, review the local preflight summary, then confirm overwrite.

iPhone/iPad → Android is the same flow. Platform device backups do not automatically cross Android ↔ Apple; use .eab for cross-platform migration.

Does restore merge with current progress?

No. Portable restore fully replaces local progress to avoid duplicate events or inflated mastery. Export the current progress first if you need a rollback copy.

Audio will not play

• Check media volume and Bluetooth output.
• End calls or other apps holding the audio session.
• Relaunch Taiwan English Lab.
• If one item is consistently silent, note the word and device model when reporting.

Version 0.1.0 does not use the microphone. In the 0.1.1 candidate, microphone access is requested only after the learner taps Record; there is no cloud pronunciation scoring.

How does optional local recording work?

In the 0.1.1 candidate, an explicit tap on Record creates at most one temporary, mono WAV clip of up to 10 seconds for local replay and comparison with built-in reference audio. The clip is never uploaded or sent to an AI service, and neither the clip nor its score is kept in SQLite, backups, exports, share sheets, analytics, or raw-audio logs. It is deleted when practice is left, cancelled, retried, or backgrounded. If cleanup fails, new recording pauses until cleanup succeeds; after operating-system termination, the controlled stale clip is removed before the next attempt.

Acoustic similarity is an experimental on-device practice cue, not pronunciation correctness, a formal score, CEFR, or learning mastery. It does not change learning mastery, and the practice cue is not retained.

Is placement an official Cambridge score?

No. It is an independent, low-pressure CEFR-aligned learning start estimate, not a formal exam result or Cambridge English Scale score.

How do I delete data?

Open Settings & Backup → Delete all local data, then complete the parental confirmation. Backups already saved to cloud/NAS storage must be deleted there by the user.