Privacy Notice
This page is for parents. The site has no accounts and no sign-in, and it never asks you or your child for a name, email, phone number or address. Here is exactly what is collected, why, and for how long.
What we collect
How the site is used: which mode was opened, which button was pressed, whether a question was answered right or wrong, the interface language at the time, and when. For example, "traced ㄅ in Trace It and got it on the first try". This is collected so we can tell which features actually help and where children get stuck.
The device identifier (deviceId)
The site stores a randomly generated identifier in your browser so that repeat visits from the same device can be joined up - that is what makes it possible to tell whether children keep coming back. It contains no name and nothing that identifies a person directly, and it is never used to follow you across other websites - Google Signals and ad personalization signals are switched off in the page code itself, see "Who the data goes to" below. It is, however, a persistent identifier, which under the US COPPA definition counts as personal information - so we commit that it will never be used for advertising targeting of any kind, and never given to anyone beyond the processor described below. Clearing your browser data removes it.
How long we keep it
Individual raw events (which include the deviceId) are kept for 14 months and then deleted. Why 14 and not 12: Zhuyin is tied to Taiwan's September school year, and a 12-month window would expire last year's data at exactly the moment you want to compare against it. At expiry the data is not simply thrown away - it is first rolled up into daily counts. Those aggregates carry no deviceId and no per-event sequence, so they cannot be traced back to any child; that rolled-up form is kept long term for year-over-year comparison.
What it is and is not used for
Internal product decisions only: what to fix and what to build next. No advertising targeting, no profiles built for outside use, no selling, and no sharing with third parties beyond Google Analytics, which processes the data on our behalf (see "Who the data goes to" below) - and no session replay, which would record your child using the screen. We do not do that.
What we never collect
Names, emails, phone numbers, addresses, birthdays, precise location, camera or microphone, contacts, or any recording of the screen or audio. The site loads no third-party ad network and no advertising tracking pixel; the only two third-party scripts are Cloudflare's traffic beacon and Google Analytics, both used solely for statistics.
What stays on the device
Stars, stickers, which symbols have been seen, and the learning report in the parents panel are all written only to this browser and never uploaded. Switching device or clearing browser data resets them.
Who the data goes to
The usage events described above are sent to Google Analytics 4 (GA4, measurement ID G-D57G392HVR), where Google stores and processes them - which makes Google a data processor for this site. To put it plainly: the data is Google's as well, our internal policy cannot govern what Google does with it, and we chose GA4 knowing that. To keep the exposure as small as possible, Google Signals and ad personalization signals are switched off in the page itself, before the analytics script loads - so they are already off for the very first request - and we never use this data for advertising targeting of any kind. GA4 also sets a cookie of its own (_ga) in your browser. The traffic figures still come from Cloudflare's cookieless beacon, which sets no cookie and carries no identifier.
Where this stands today
These are the only two analytics tools the site uses: Cloudflare Web Analytics (cookieless, aggregate traffic figures) and Google Analytics 4 (the usage events above). Nothing else receives usage data, and no other third party can get at it. If we ever change or add a tool, this page will be updated to name the recipient again.
Last updated: 2026-07-31