Start with one free story
Choose a Story group, then Story 01. Tap a known fact and place it in Start, Change or Now. Place both facts, choose Add or Take Away, select the unknown slot, and choose a prediction from 0–20. Submit before checking the result. If you change your model, submit again before playback.
Play forward and undo
Play the model you submitted, then undo its change. Read the matching quantities and equations. A wrong prediction does not secretly play the correct model. Review the story and your placements, edit your model, and try again. A completed story and a first independent correct response are recorded separately.
Parents, learner profiles and sound
Open Parents and follow three changing hold-and-release instructions. Leaving Parents or backgrounding the app ends that authorization. Parents manages up to four profiles, nicknames, preset avatars, Read stories aloud and learning records. Use a nickname only; do not enter a child’s full name, birthday, school, email or contact details. Prerecorded audio never records your child. Written stories remain available with sound off.
Full Unlock and Restore Purchases
Six stories remain free, one per structure. Full Unlock is a US$6.99 one-time purchase for the other 42; it has no subscription or automatic renewal. In Parents, Apple shows the current localized price. If the price cannot load, connect and use Reload Price. Use Restore Purchases with the Apple Account that purchased or is eligible for Apple Family Sharing. Pending purchases unlock after Apple approves them. Purchase restoration restores access, not learning records. Do not delete the app to troubleshoot a purchase.
Backup and validated import
In Parents, Export Learning Backup saves JSON to a destination you choose. Import Learning Backup validates a file and shows a preview before restore. A local recovery copy is saved first. Invalid data is rejected without replacing your existing learning store. Backups contain learning records and settings, never purchase entitlement or Apple receipts. The app does not password-encrypt exports; keep them private. Before changing devices, export a backup and confirm that you can access the file.
Optional private iCloud
Sync learning records with iCloud is off by default. A parent can enable it for devices using the same iCloud account. Profiles, submitted models, help events and completed learning can sync; an unfinished draft stays on its original device. If iCloud is unavailable or storage is full, local learning continues and the status explains the problem. Turning sync off stops learning uploads and fetches; it does not erase earlier cloud copies. Family Sharing purchase access is separate from private iCloud learning.
Delete learning records
Parents can confirm deletion of one learner or all learners. The app removes the selected local learning and cleans its automatic recovery copies. An identifier-only deletion marker prevents older synchronized records from restoring deleted learning. When sync is on, private cloud deletion is requested and remains pending until sync succeeds; other devices keep their copies until they sync. When sync is off, previous cloud copies remain. Exported files and operating-system backups are managed separately. Verified purchase access is retained. If cleanup or saving fails, read the status before trying again.
Contact support
A parent can email the app version, device model, system version and a short description of the issue. Please do not send children’s real names, photos, voices, learning backups, payment details or other personal information. StoryUndo is in internal testing and is not publicly available on the App Store. A support page is not a download invitation.