Privacy
Cell Diagrams is made for students to use. There are no accounts, and we never ask for a name, email, or other personal details. Here is exactly how information is handled:
- Practice happens entirely in your browser. Answers are checked on your device, and we never receive a score or anything a student types. The one exception is a problem report, below, which says how the app marked the question on screen. A typed answer box accepts only letters, spaces, hyphens and apostrophes.
- Every page has a Report a problem button. A report is sent only if someone taps Send, and it holds no name and nothing anyone typed. It says which page it came from, which version of the app, and a few facts about the browser window, like its size. Sent from a practice question, a flashcard or Label the Cell, it also says the part and cell on screen, the kind of question, how the drawing is shown, how the part is answered, the four choices where there are four, and whether the app marked it right or wrong (“I don't know” counts as wrong) or was in the fix step after a miss, with the part or answer the app registered a tap on. All at once, Label the Cell says only whether the labels have been checked. For a typed answer marked right, it says whether it was accepted as a close spelling, and so a reader can work out that what was typed was that part's name. Sent from the Explorer, it says the cell, 2D or 3D, the parts shown and the part picked. Sent from a setup or results screen, it says the settings. A report never includes what was typed, a score, the question's number, how long the set is, whether a question is coming back, or the parts of a “Practice these again” set. The full list is in the Model Teaching Apps Privacy Notice.
- When you make a worksheet, the options you chose (the packet, the cells and parts, the cell or comparison, the answer style, the job wording, the lysosome sorting choice, the answer strip and answer key, the version letter and the number of versions) are sent to our server so it can build the PDF. They are all choices from fixed lists: nothing a person typed is sent, not even a saved worksheet's name, and practice results are never sent. We use the options to make the file and do not store them.
- The diagrams and the 3D cells are drawn by your browser from this app's own code. Nothing is downloaded from any other site, and no AI runs while you use this app.
- We use one analytics service, Fathom Analytics. It counts page visits without cookies and without tracking individual people. There are no cookies anywhere on this site, so there is nothing to accept or dismiss. You can switch analytics off for your browser from the Model Teaching Apps Privacy Notice.
What this app saves in your browser
Everything is saved under names that start with mt_celldiagrams_, and Settings can erase all of it at once. The one exception is your light or dark choice, saved as theme, which stays until you clear your browser's data.
| What | Details |
|---|---|
| Saved builds | The practice setups you chose to save: which cells and parts, the activities, the answer style and the other options, with a name made of letters only. Never a score or anything typed in practice. |
| Saved worksheets | The worksheets you chose to save: the setup (cells, parts and options), the packet, the cell or comparison, the version letter, the number of versions, the answer strip and the answer key choice, with a name made of letters only. |
| A worksheet about to open | When you open a saved worksheet, its choices are handed to the builder. Kept in this tab only and erased as soon as the builder reads them. |
| The practice set in progress | The items in order, which one the student is on, right or wrong so far, which part was picked on a miss, and the time spent, so a refresh doesn't lose the set. Kept in this tab only, and erased when the set ends, the student exits, or the tab closes. What a student typed is not kept. |
| A setup about to start | The choices you made on the setup screen, handed to the practice screen. After "Practice these again", also which parts to practice again. Kept in this tab only. |
| Settings | Theme, celebration effects, motion, and Clear on close. |
| A random device id | Made in this browser and never sent anywhere. It keeps your saved builds grouped on this device. |
Children's privacy. This app is built to collect as little as possible from children. There are no accounts, no cookies, and nothing a child types is sent to us or stored by us. Parents, teachers and schools can read the full detail, including what our hosting and analytics providers receive and how long they keep it, in the Model Teaching Apps Privacy Notice, which also lists how to contact us.
You can erase everything this app has saved in your browser from its Settings page, or erase every Model Teaching app at once from the notice linked above.
Last updated: November 11, 2026. Most recent change: we described what a problem report includes.
Questions about data? Reach us through the contact page.