vehiVehi Support
Getting started
Choose Scan, Photos or typed input. Crop, rotate and review your image. After recognition, edit the complete problem once and request visualization. Problems that do not benefit from a diagram can use algebra or another suitable representation.
Interact and solve
Drag free points, pinch to zoom and rotate 3D models. Dependent objects are recomputed. Reset restores the initial view. Solve opens a step-by-step explanation while keeping the mathematical workspace available.
Credits and purchases
Default prices: recognition 1 credit, visualization 5 and solving 5. Server-configured prices are shown before an operation. Reviewing saved work and interacting with a scene is free. Packs contain 80, 200 or 450 credits and use Apple IAP. Apple supplies the actual localized price. Link Sign in with Apple before purchasing. Purchased credits do not expire.
Failed or uncertain results
Keep the recognized text, improve the image or edit the problem. Technical errors, cancellations and unsuccessful paid artifacts are refunded. An unverified scene is not presented as correct. You can still request a solution where possible.
Report a drawing or solution
Tap the flag in the workspace and choose Drawing error or Solution error. Comments are optional. Detailed artifacts and images are opt-in. Confirmed errors may qualify for an operation-credit refund; duplicate reports do not create unlimited refunds.
Pending credits
Do not purchase again to fix a pending delivery. Reopen the app with the same account to retry verification. The client finishes a StoreKit transaction only after backend delivery. Avoid uninstalling before linking Apple ID.
Apple refunds
Request a purchase refund at https://reportaproblem.apple.com. Apple decides eligibility. Refunded or revoked purchases remove their corresponding credits. If those credits have already been spent, the balance may become negative and further spending is paused.
Delete data or account
Open Settings → Data and privacy → Delete images and history or Delete account. Account deletion removes content, invalidates access and unlinks Apple identity. Pseudonymous financial records remain for reconciliation. Consider unused credits before deleting.
Official contact
Developer: Binh Hoang Yen. Official support: hybinh.dev@gmail.com. Contact us about account, credit or privacy questions. Do not include passwords, API keys or card details. Use in-app error reports for mathematical errors so the relevant artifact version is included.