Privacy

When you add a timetable from a screenshot or a photo, your phone reads it. The image is never uploaded, and we never see it. We never ask for your CUSIS login.

• For each group: its name and settings (days, hours, meeting length, walking time), when it was made, its 4-digit PIN, and scrambled keys for the people who manage it.
• For each person in a group: the name they type, their busy times and, unless they turn it off, class names, types and rooms; when they last changed it; and a scrambled key that lets their phone edit it.
• No accounts, emails or phone numbers. No ads, and no cookies except one that remembers the language you choose.

Anyone with a group’s link can see the group: everyone’s names and timetables, with class names and rooms where they are shared. Anyone with the link can also rename the group and change its settings. Only you, or a manager with the group’s PIN, can change or remove your timetable. Share the link only with people you trust.

A group, and everything in it, is deleted automatically when nobody opens it for 30 days. You can remove yourself from a group at any time, and a manager can delete the whole group.

This browser keeps the keys for the groups you made or joined, so it remembers you. If you choose “Save on this device”, your timetable is kept here too, to join your next group in one tap; “Forget it” removes it. Clearing this site’s data forgets both.

• Vercel runs the site, in Singapore. Like any website’s, its servers see your IP address when you visit.
• Upstash stores the groups.
• Vercel Web Analytics and Speed Insights count visits and time how fast pages load, without cookies. They are told which kind of page you opened, never a group’s link, and they don’t tell us who you are.
• jsDelivr sends your phone the text-reading engine the first time you read a screenshot. It sees your IP address, never your image.
• To stop abuse, we keep a scrambled form of your network address (never the address itself) for a few hours at most.

夾時間 is an independent project by jengmap. It is not run or endorsed by CUHK.

Email leoc@link.cuhk.edu.hk. To have a group deleted, send us its link.