Last updated 27 October 2026.
At a glance
| What | Where it goes | How long |
|---|---|---|
| Your voice | Turned into text by Apple’s speech recognition, on your phone. The audio never leaves it | Never kept |
| Your tasks, board and logbook | Your phone | Until you delete them |
| Backup, if it is on | One snapshot of your app’s data on our server, under an anonymous token | Until the next backup replaces it, or you delete it |
| Text checked for heavy topics | Our server, then TypeSafe | Not stored, not logged |
| Text for a fresh line | Our server, then DeepSeek: the task’s words only | Not stored by us |
| Your calendar | Read on your phone only | Never leaves your phone |
| Purchases | Apple and RevenueCat, with an anonymous id | While you have tuition, and as Apple’s records require |
| Notes home | An Apple notification token on our server | Until you turn notes off or delete everything |
| Crash reports | Sentry, in the EU | 90 days at most |
Who we are
Phu’s Class is made by Odd Eggs Studio, which is responsible for the data described here. Write to privacy@phusclass.com about anything on this page.
Hearing you
When you hold to talk, Apple’s speech recognition turns your words into text on your phone, set to work on the device only. The audio never leaves your phone and is never kept, by us or by the app. You can always type instead.
Your tasks
Everything you say or type, the board, the logbook and your desk live in a database on your phone. There is no account and no sign-in.
If backup is on, the app sends one snapshot of that data to our server so it can come back on a new phone. It is stored under an anonymous backup token kept in your iCloud; our server keeps only a fingerprint (a hash) of that token, not the token itself, and nothing that says which phone sent it. Each backup replaces the one before. A snapshot is at most 512 KB. Delete everything removes it.
Checking for heavy things
Before Thầy Phú says anything pointed about a task, its text is checked for crisis or heavy topics, so that the act can stop. Your phone checks first, with no connection. When you are online, the text is also sent to our server and from there to TypeSafe, a service that judges it. If TypeSafe does not answer, DeepSeek answers in its place. If Vietnamese was typed without tone marks, DeepSeek may first restore them so it can be read properly.
This text is not stored and not logged on our server, and it is never used to train models.
His fresh lines
Most of his lines are written in advance and come from the app itself. When you are online and a task is one he has no good line for, our server asks DeepSeek to write one. Only the task’s words are sent, with no name, device id or anything else about you. We do not store them.
Your calendar
If you open the timetable and allow it, the app reads your calendar events on your phone to lay out the day. They never leave your phone, and the app never changes your calendar.
Your device, to our server
The first time the app talks to our server it makes a random device token. Our server keeps only a hash of it, the app’s language, and when it was first and last seen. It is not linked to your name, email or Apple Account.
For each call to a model we record the route, the model and the number of tokens used, never the text, so we can see what the service costs. When you delete everything, those records are cut loose from your device.
Purchases
Apple takes every payment; we never see your card. RevenueCat keeps track of whether you have tuition, under an anonymous id our server makes from your device token. Our server keeps whether tuition is active, which plan, and when it ends.
Notes home
If you let him send notes home, Apple gives the app a notification token, and our server keeps it, with the app it belongs to, so the notes can reach you. A Live Activity has tokens of its own, kept the same way while it runs. Turn notes off or delete everything and they go.
Photos
The app only ever adds a card you choose to save to your photos. It never looks at the rest.
Crash reports
When the app breaks, a report goes to Sentry, stored in the EU: what broke and where in the app, your iPhone model and iOS version. It is set up to leave out your name, your tasks and anything you typed. Reports are deleted after 90 days at most.
What we never do
No ads. No tracking across apps or websites. No selling or sharing your data for marketing. Nothing you say is used to train models. The services named here are used only to run Phu’s Class.
Export and delete
In the app’s settings you can export everything into one file, and delete everything. Deleting removes your data from your phone, and from our server it removes your device’s record, its notification tokens and your backup at once. Crash reports expire on their own within 90 days. Deleting does not cancel tuition: that is in your Apple settings.
You can also write to privacy@phusclass.com to ask what we hold, to correct it or to delete it. Because there are no accounts, we may need your help to find what is yours.
This website
phusclass.com sets no cookies and runs no analytics. The chalkboard on the home page works entirely in your browser: nothing you type there is sent anywhere. Our host, Cloudflare, handles requests to serve the pages.
Children
Phu’s Class is not for children under 13, and we do not knowingly collect data from them.
Changes
If this policy changes, the new version goes here with a new date. If a change matters to how your data is used, the app will tell you first.