Privacy policy

What we keep

• A random ID in a cookie in your browser, so Leizi can recognise your browser and keep your progress without an account.
• Your learning records: when you first opened Leizi, how you marked each word, which options you chose in stories, when you moved past each card, and when you finished each lesson.
• Whether you opened Leizi on a phone, tablet or computer, and which app it opened in, such as Messenger. We keep only these two labels, not your device details.
• Your explanation language, saved in your browser.
• The link that brought you to Leizi, when the link names its source, such as an ad.
• If you message the Leizi Facebook Page: the ID Messenger gives you for this Page and the ad that brought you, so we can send your learning link and tell you when your next lesson opens.
• If you sign in with Facebook or Google: the name, email address and profile picture that service shares with us, and the account ID it gives Leizi. We never see your password.
• Error reports when something on the site breaks. They describe the error and do not include your IP address or device details.

Why we keep it

We use this information to save your progress, open the next lesson at the right time, show your completed lessons on other devices after you sign in, and count how many people start and finish lessons and where they stop, so we can improve Leizi. We do not sell your information.

Who handles it

Leizi stores data with Supabase (database and sign-in), runs on Vercel (hosting), uses Sentry (error reports) and runs the Leizi Facebook Page chat on Botcake by Pancake. These services may store data outside Vietnam. Our hosting providers may keep standard server logs, such as IP addresses, for a short time for security.

Leizi uses Meta Pixel, which tells Meta (Facebook) when you open Leizi and when you start or finish a lesson. Meta uses this to measure our ads and show them to people who may want to learn, and handles it under its own privacy policy.

Delete your data

If you signed in, email weizhihao2024@gmail.com from your account's email address and ask us to delete your data. We delete your account and every learning record linked to it within 30 days and reply to confirm. If you signed in with Facebook, you can also remove Leizi under Settings › Apps and websites on Facebook. If you chatted with the Leizi Page, you can also ask in that chat.

If you never signed in, your records are linked only to the random ID in your browser. Clearing your browser's data for leizi.space removes that link.

Who runs Leizi

Leizi is operated by 灵能飞升（深圳）科技传媒有限公司, 深圳市福田区福田街道福安社区民田路178号华融大厦720H25, China. It is responsible for the information described on this page.

Contact

Questions about this policy: weizhihao2024@gmail.com