Privacy policy
Alô Saigon is a small app for learning southern Vietnamese, made by an independent developer (“we”, “us”). We built it so that your learning stays on your phone. This page explains exactly what the app stores, what it sends, and when.
The short version
- No account, no ads, no analytics or tracking tools.
- Your progress and settings are stored only on your device.
- The microphone is used only in Say it. Your voice is analysed on your device and is never uploaded.
- The only thing the app sends over the internet is a feedback report, and only after you tap Send.
- Uninstalling the app (or clearing the web app’s site data) deletes everything it stored.
1. What stays on your phone
The app saves the following in its own private storage on your device. We can’t see any of it.
| Learning progress | Which words you’ve started, your review history and schedule, streak, sessions, Tone Gym answers, pinned topics, and your settings (daily goal, voice, speed, theme, reminder time). |
|---|---|
| Say it calibration | A few numbers that describe your voice’s pitch range, plus your scores per tone. No recordings. |
| Feedback on the phone | An anonymous tester ID, the name or email you typed in the feedback form (if any), an unsent draft, and reports waiting to be sent. |
| Crash notes | Short technical notes about the last 10 errors the app caught, so a feedback report can include them. |
2. Backups
Backups you make
In Settings › Backup you can tap Share backup. The app writes your progress and settings to a .json file and opens your phone’s share sheet. Where the file goes (Drive, email, a chat) is your choice and is governed by that service. You can restore it with Restore from a backup file or by pasting the text. The app never uploads a backup by itself.
Your phone’s own backup
If you have turned on your phone’s system backup (for example Google’s backup on Android, or iCloud backup on iPhone), the operating system may include the app’s stored data in that backup, in your own account. This is controlled by your phone settings, not by us, and we can’t access it.
3. Microphone and Say it
- The app asks for microphone permission only when you open Tones › Say it and choose to turn the microphone on. Everything else works without it.
- The microphone is on only while you are recording a take after tapping the mic. It is turned off when the take ends, when you leave the screen, and when the app goes to the background.
- Your voice is turned into a pitch curve on the phone. The sound is never uploaded or sent anywhere.
- So that you can tap Mine to hear yourself, your most recent take is kept as a temporary audio file in the app’s cache. The next take overwrites it, and it is removed when the app’s cache is cleared or the app is uninstalled. It never leaves your phone unless you share it yourself.
4. Sharing a Say it card
After a take you can tap Share. The app draws an image of your pitch curve next to the reference curve, with the syllable and your score, and opens the share sheet. It contains no audio. Nothing is shared unless you pick an app to share it with.
5. Daily reminder
If you choose a reminder time, the app schedules a local notification on your phone, once a day at that time. Your phone may ask you to allow notifications. The app does not create or send a push token, and no server sends you notifications. Turning the reminder off cancels it.
6. Audio and text-to-speech
The word and tone audio is built into the app, so it plays without an internet connection. Where a sound has not been added yet (for example some example sentences), the app asks your phone’s own text-to-speech engine to read the Vietnamese text aloud. That engine is part of your phone’s system (for example Speech Services by Google), and its own settings and privacy terms apply. The app passes it only the Vietnamese text to speak.
7. The web app
The web app at alosaigon.com/app is the same app running in your browser. Everything above applies, with these differences:
- Storage: the items in section 1 are kept in your browser’s storage for alosaigon.com on that device, not on our server. Clearing the site’s data in your browser deletes them. If you install the web app, your browser may also keep a copy of the app’s files so it opens quickly and works offline.
- Loading: the app’s files, including the audio, are downloaded from alosaigon.com, which is hosted on Cloudflare (see section 12).
- Microphone: your browser asks whether alosaigon.com may use the microphone. Your voice is analysed inside the browser and never uploaded. Your latest take is kept only in the page’s memory for Mine and is gone when you close or reload the page.
- Sharing a card saves the image to your device instead of opening a share sheet.
- Daily reminder is not available in the web app.
- Text-to-speech uses your browser’s speech voices. Some browsers offer online voices (for example the “Google” voices in Chrome); if one is used, your browser sends the text to be spoken to its provider.
- Backups are made with Download backup or Copy in Settings › Backup.
8. Feedback reports
You can send us a report with the speech-bubble button at the top right of the app’s screens, or from Settings › Feedback › Send feedback. This is the only feature that sends data from the app over the internet, and it happens only when you tap Send (shown as Save report in test builds where sending isn’t switched on yet).
What a report contains
| Type | Bug, Confusing, Audio / pronunciation, Idea or Other. |
|---|---|
| Message | What you wrote. |
| App version | Version and build of the app, and the platform (Android, iOS or web). |
| Tester ID | A random ID such as T-7KQ2-M9XD, created once when the app is installed and stored on the phone. It is not linked to your name, account or device identifiers. |
| Contact | Only if you typed a name or email in the optional field. It is remembered on your phone for next time. |
| Screen | Which screen you were on and, during a lesson, the exercise type and word. Only if “Include what I was doing” is on. |
| Device | Phone model and operating system version (for example “Google Pixel 7 · Android 14”; in the web app, the operating system the browser reports). Never the phone’s name. Only if “Include what I was doing” is on. |
| Details | A report ID and time, the screen and its parameters, app and system versions, language setting (such as en-US), 12- or 24-hour clock, theme, screen size and text size, a few progress counts (words started, practicing, familiar, learned, known; streak; day number; sessions; tone answers), the last ~20 steps in the app (screens visited and answers given), and the last 10 crash notes.With “Include what I was doing” off, Details contains only the report ID and time. |
Tap See details in the feedback form to read the exact text before you send it. A report never includes your recordings, your full progress, your location or time zone, your contacts, or any account information.
Where it goes
The app sends the report directly to a Google Form operated by us, which stores it in a Google Sheet that only we can access. Google hosts these for us, and Google’s privacy policy applies to that hosting. Like any internet connection, the request reveals your phone’s IP address to Google; it is not part of the report and we don’t see it.
A report is saved on your phone first and sent when you tap Send. If you’re offline, the app keeps it and tries again later (when you open the app or come back online). In test builds where sending isn’t switched on yet, reports stay on the phone and are sent automatically once you install a build that can send them. You can also tap Copy report to paste it into an email or chat yourself.
We use reports only to fix problems and improve the app. We keep them as long as they are useful for that and delete them when you ask.
9. What we don’t do
- No accounts or sign-in.
- No advertising, and no analytics, tracking or crash-reporting services. Crash notes stay on your phone unless you send them in a report.
- No location, contacts, photos or other personal data are read.
- We don’t sell or share your data, and we don’t use it for advertising.
10. Children
Alô Saigon is not directed at children under 13, and we do not knowingly collect personal information from them. The app asks for no personal information. If you think a child has sent us a feedback report with contact details, email us and we will delete it.
11. Deleting your data
- Everything on your phone: uninstall the app. On Android you can also go to Settings › Apps › Alô Saigon › Storage (or Storage & cache) › Clear storage.
- Web app: clear the site data for alosaigon.com in your browser’s settings (removing the installed web app alone may not clear it).
- Learning progress only: Settings › Danger zone › Reset progress erases your words, reviews and streak. It keeps your settings, your Say it calibration and your feedback tester ID.
- Feedback you sent: email hello@alosaigon.com with your Tester ID and we will delete your reports. The Tester ID isn’t shown on a settings screen: after you send or save a report, tap Copy report and it appears in the copied text as “Tester: T-…”. If you don’t have it, tell us roughly when you sent the report and what it said, or the contact you entered.
12. This website
The pages of alosaigon.com outside the web app are static, with no cookies, no analytics and no forms. It is hosted on Cloudflare, which processes standard request information (such as IP addresses) to deliver and protect the site. Fonts are loaded from Google Fonts, so your browser connects to Google to download them.
13. Changes and contact
If the app starts handling data differently, we will update this page and the effective date above before that version is released.
Questions or requests: hello@alosaigon.com.