Question 1

Does it work without internet?

Accepted Answer

Yes. After opening online once, it runs on a single device even with no connection (outdoor events, markets, etc.). Data is stored on your device and never sent anywhere.

Question 2

Do customers need a dedicated app?

Accepted Answer

No. Customers just show a paper QR card (or member number). No app install or member-site login is required. Everything is handled on the shop's device.

Question 3

Where is member data stored? Could it leak?

Accepted Answer

Members, stamps, punch cards and history are all stored inside your browser (IndexedDB) and never sent to a server. No third party can access the data. When entering personal info like names, take care with how the shop device is managed.

Question 4

Is data lost if I switch phones or browsers?

Accepted Answer

Clearing browser data or moving to another device does not carry data over. Take a JSON backup from the Settings tab and restore it on the new device.

Question 5

QR scanning doesn't work.

Accepted Answer

On a device with a camera, major browsers on PC and phone can read QR codes (a fallback decoder is built in for unsupported browsers). If it won't read, use manual entry via “Open by code” or pick from the Members list. If the camera won't start, check that you're on HTTPS and that camera permission is granted.

Question 6

I added too many stamps.

Accepted Answer

Use “Undo one” below the Add stamp button in Member details to roll back one at a time. Undo actions are kept in history too.

Question 7

Can I change the stamp goal or reward later?

Accepted Answer

Yes, anytime from the Settings tab (1–60). Changing the goal applies to the slots from then on. Stamps already collected are kept as-is.

Question 8

What do I do for a customer who lost their card?

Accepted Answer

From Reissue card in Member details, you can show the same member QR again. Choose PNG save or print; stored stamps, punch cards and history carry over.

Question 9

I want to use the same member data on two devices.

Accepted Answer

For now each device stores independently. To share, export a JSON backup from Settings and restore it on the other device. For day-to-day use we recommend designating one primary device.

Question 10

I want to manage the member list in Excel.

Accepted Answer

From the Settings tab you can export the member list and history as CSV (UTF-8 with BOM), openable directly in Excel or Google Sheets.

Stamp & Punch Card