Each detail looks harmless. Together, they add up.
Every app can read these without asking you first. Combined, they can work as a device fingerprint that recognises you across apps.
- When your phone was set up, to the second
- When it last restarted, to the second
- Free space, to the byte
- Your headphones’ name, which often holds your first name
- Your languages and keyboards
- Which apps you have, asked about one by one
Grant a permission and an app can see far more. And any app can ask whether specific apps are installed — an answer that could reveal your dating life, your health, your faith or your money.
A calm look at your footprint.
Scan
Reads nearly 50 details any app can read without asking, grouped by what they reveal. A calm footprint score out of 100 counts only what you can change.
Every clue explained
For each one: what an app learns, why the system allows it, and how long it lasts — until you restart, or until you erase the phone.
A fix for each finding
Plain steps for what you can change. Where only Apple can fix something, it says so honestly instead of pretending.
What apps see once you say yes
Ten permissions, from Location and Photos to Contacts and Local Network. Tap “Show me” on one to see exactly what an app would get — it asks only then, never when the app opens. Contacts, calendars and photos appear as counts and summaries, never contacts' names, numbers or event titles.
Which apps give you away
Choose which of nine sensitive categories to check: dating; religion and faith; health and fertility; addiction and recovery; VPN and censorship tools; private messaging; crypto and gambling; job hunting and workplace; politics and news. All are off until you switch them on, results stay blurred until you tap, and they are cleared when you leave and never saved.
Guided permission check-up
The system never tells one app which other apps can reach your Health data, location or photos — only Settings knows. A 12-step walk through Settings covers it, starting with Safety Check.
Keep track
Scan again to see before and after. History stays on your device as scrambled markers, never the values, and is left out of backups. A scoreboard shows what Apple has closed and what is still open, and a share card carries your score and none of your values.
The detective
A blue furry detective lives on every page. He leans when you tilt your device, and gives you a tip when you tap him.
What you will see.
It shows you everything. It keeps nothing.
The App Store privacy label is Data Not Collected. There is no account, no sign-up, no hYYa server, no analytics and no third-party code. Everything the app reads is shown to you on your device and stays there. A few features use Apple’s own services, such as your App Store country — the privacy policy names each one.
Read the privacy policyDon’t take our word for it.
The code is published under the Mozilla Public License 2.0, so anyone can read it and check every claim on this page.
Read the code on GitHubFrequently Asked Questions
What can apps learn about my phone without asking?
Dozens of details: when your phone was set up and when it last restarted, to the second; its free space, to the byte; the name of your headphones; your languages and keyboards; and many more. hYYa Footprint Inspector reads nearly 50 of them and shows you each one in plain language.
What is device fingerprinting?
It is combining many harmless-looking details into a pattern unusual enough to recognise one device across apps. No single detail gives you away; together they can.
Can an app see which other apps I have installed?
It can ask about specific apps, up to a limit the system sets, and the answer can reveal your dating life, your health, your faith or your money. No app can list everything you have installed; hYYa Footprint Inspector shows you which sensitive categories can be detected.
Can apps learn my name from my headphones?
Often, yes. Headphones and speakers are frequently named after their owner, such as "Sam's AirPods", and any app can read that name without asking. hYYa Footprint Inspector flags it and shows how to rename them.
Can hYYa Footprint Inspector see which apps have access to my Health data or location?
No. The system never tells one app which other apps can reach your Health data, location or photos; only Settings knows. The guided check-up walks you through those Settings screens one at a time, starting with Safety Check.
Is it a spyware or virus scanner?
No. It shows what any app can read about your device, and how to reduce it. It does not examine other apps or look for malicious code.
Does it collect or send any of my data?
No. Its App Store privacy label is Data Not Collected, there is no account and no hYYa server, and nothing the app reads leaves your device.
Why does it ask for permissions?
Only to show you what an app would get if you said yes. It asks for each permission when you tap "Show me", never when the app opens, and for contacts, calendars and photos it shows counts and summaries, never contacts' names, numbers or event titles.
What does the footprint score mean?
Everyone starts at 100, and the score drops only for findings you can change. Things only Apple can fix are listed separately and never lower it, so the score always points at something you can do.
Is it free and open source?
Yes. It is free, with no in-app purchases, no subscription and no ads, and its code is published under the Mozilla Public License 2.0 on GitHub, so anyone can read it to check these claims.
What do your apps know about you?
Find out, then fix it. Free, open source, and nothing leaves your device.
Get it on the App StoreFree · open source · no in-app purchases