Privacy Policy

Last updated: September 28, 2026

System Guard is made by RBT Digital LLC ("we", "us"). This policy explains what the app reads, what it keeps, what it sends and to whom, and what you can control. It applies to the System Guard app for iPhone and iPad, version 26.9.1 and later, with its widgets, its Control Center controls, its share extension, and its Apple Watch app, and to the website www.systemguardapp.com, including its help pages.

The short version: System Guard has no account and reads only what Apple makes available to every app. What it reads about your device stays on your device - the model, the addresses, the Wi-Fi name, the devices on your network, the test results, the history, the traffic figures, and the battery figures from files you import - except inside a support message you write yourself. The free version shows ads from Google AdMob, and the app reports usage statistics without device values, and crash reports, to Google Firebase. You decide about personalized ads, and System Guard Pro shows no ads at all.

1. Who is responsible

RBT Digital LLC, 30 N. Gould Street, Ste 6045, Sheridan, WY 82801, United States, publishes System Guard, runs this website and the app's server, and is responsible for the data described here (the "controller" under European law). Questions about this policy and requests about your data: our contact form.

2. What the app reads on your device

The app's purpose is to show you what your device is and what it is doing. To do that it reads, through Apple's public frameworks, the model and its identifier, the iOS version and build, the kernel version, uptime, CPU load, memory and storage figures, battery level and state, Low Power Mode, thermal state, display properties, chip and GPU properties, the sensors, cameras, and audio route the device has, whether a passcode and Face ID, Touch ID, or Optic ID are set up, the network state (interfaces and their addresses, DNS servers, router, cellular technology, VPN state, and, if you allow it, the Wi-Fi network name and access point address), and the byte counters iOS keeps for each network interface.

All of this is shown to you and stays on your device. It is not transmitted to us or to anyone else, with two exceptions that are your choice: the device report you can attach to a support message (section 8) and the report you can export yourself (section 11).

3. What the app keeps on your device

The app keeps the following on your device, in its own storage and in a container it shares with its widgets, controls, and share extension on the same device:

The check-up verdicts you give (passed, failed, skipped), until you tap Clear results.
History, part of System Guard Pro: a reading of free storage, memory in use, thermal state, and battery level, taken when you open the app and when one of its widgets refreshes, at most one every 20 minutes, kept for 90 days or until you tap Clear history.
Network traffic: per-day totals of the data the whole device sent and received, split into Wi-Fi or wired and cellular, for the last 30 days. They are worked out from the interface counters in section 2. iOS does not tell apps which app used the data or where it went, and System Guard does not know either.
Battery health readings and the list of imported files (section 4).
Your settings, such as the alert thresholds, and whether you own System Guard Pro (section 11).

The Apple Watch app reads the watch's own figures the same way and receives the iPhone's status card (iOS version, free storage, memory in use, battery level, Low Power Mode, thermal state) from the iPhone over Apple's device-to-device link; it keeps that card on the watch. The widgets, the Control Center controls, and the Shortcuts actions read the same figures on the device.

Alerts: History can notify you when free storage falls below a limit you choose and when a newer iOS is available for your model. Both are off until you switch them on, and iOS asks for permission to send notifications at that moment, not before. They are local notifications, decided and scheduled on your device. There are no push notifications, and no notification token is sent anywhere.

Deleting the app removes everything it stored on the device.

4. Battery health from iOS's analytics files

When Share iPhone & Watch Analytics is switched on in Settings › Privacy & Security › Analytics & Improvements, iOS writes a diagnostics file every day and lists it under Analytics Data, together with the files of a paired Apple Watch. That setting, and what iOS sends to Apple under it, is between you and Apple. System Guard does not change it and never receives anything Apple collects.

You can hand such a file to System Guard yourself, either by tapping Import analytics files in Battery health or by sharing the file from Analytics Data to System Guard, which the app's share extension handles. Both ways work exactly alike. The app reads the file on your device and looks for its battery record. From that record it keeps only the battery figures: the date and time of the reading, the kind of device (iPhone, iPad, or Apple Watch) and its system version, the cycle count, the maximum capacity and the capacity figures behind it, the lowest and highest charge level of the day, the lowest, highest, and average temperature, the lowest and highest voltage, the highest charge and discharge current, the total operating time and screen-on time, the date of first use and the week of manufacture, the number of unexpected shutdowns, and whether the battery is reported as original and whether its serial number has changed (not the serial number itself). For every file it also keeps the file's name and date, when you imported it, and whether it carried a battery reading, so that you can see which files you have already imported.

Everything else in the file, which can include information about how apps and the system were used, is ignored and not stored. The file itself is not kept: it is read once and discarded. The battery figures stay on your device. They are never uploaded, not sent to analytics, and not part of the device report. You can delete a reading in Battery health at any time; deleting the app deletes them all.

5. Devices on your local network

Local network, part of System Guard Pro, lists the devices on the network you are connected to - printers, speakers, TVs, and anything else that answers. It works only when you start it. It listens for devices that announce themselves on the network (Bonjour) and learns their names and what they offer, and it can ask each address of your current Wi-Fi network whether a device is there. It reports only that a device is there. It does not read what a device is running and does not change anything on it. iOS asks for local network permission the first time. The list is shown on screen and is not stored or sent anywhere.

6. Requests to our server

The app talks to our server at api.rbtdigital.com for four things. Every request is signed so that only the app can use the service, and none of them carries data about your device beyond what any internet request carries (your IP address and the app's version).

Public IP address. When you open the Network tab, the app asks our server which address it was contacted from and shows it to you, together with the name registered for it in reverse DNS. That is the only way an app can learn its public address. The address is answered and not stored. If we configure a geolocation database (MaxMind GeoLite2) on the server, the country and provider are looked up on our server from the address and returned the same way; nothing is sent to MaxMind.
iOS version list. Once an hour at most, the app asks whether Apple offers a newer iOS for your model. Our server mirrors Apple's public release list; your device does not contact Apple for this, and the request carries the model identifier (for example "iPhone17,1") and nothing else.
Device list. Once a day at most, the names and specifications of Apple's models, so that a new model shows its name without an app update. Nothing about your device is sent.
App Attest. On first launch the app asks Apple's DeviceCheck service to attest that it is a genuine copy of System Guard on a genuine device, and our server verifies that attestation. Apple's privacy policy covers what Apple receives. Our server keeps the attestation key's identifier and public key (random values, not tied to you), a counter, and when the key was created and last seen, to recognize the installation on later requests.

What the server keeps: to prevent abuse it keeps a counter of requests per IP address for up to 24 hours and a short list of request nonces for a few minutes. The web server's standard access log (IP address, time, requested path, app version) is kept for 14 days and used only to operate and secure the service. No profile, no history, and no device data is stored.

7. Speed test (Cloudflare)

The speed test runs only when you start it. It measures the time to open a connection to 1.1.1.1, then downloads from and uploads to Cloudflare's public speed-test servers (speed.cloudflare.com): up to 8 seconds of download, at most 300 MB, and an 8 MB upload. Cloudflare sees your IP address as any web server does; no other data is sent. On a metered connection the app tells you before you start that the test counts against your data plan. Cloudflare's privacy policy: https://www.cloudflare.com/privacypolicy/.

8. Support messages

When you use More › Send feedback in the app, it sends your message, your e-mail address, your name if you typed one, the model and name of your device, its iOS version, the app version and language, whether you own Pro, and, if you leave the switches on, the device report (the Device and Network details and the check-up results as text) and a screenshot you picked, through our server to our support address. If you ask for a copy, the same message is sent to your address. The message also carries a random identifier of the installation (not a device identifier; it changes when you reinstall) so that the server can allow one message a minute; the server keeps it for that minute, and it stays in the mail as part of the message. Battery health readings, the history, the traffic figures, and the list of devices on your network are not part of the message.

The contact form on this website sends your name, e-mail address, and message to the same address through our web server, after Google reCAPTCHA has checked that the sender is a person (section 13).

We use the message to answer you. It is kept in our mailbox for at least twelve months, so that a later question about the same matter can be answered in context, and deleted when it is no longer needed. The device report is sent only if you leave "Attach device report" on; you can read it before sending under More › Device report.

9. Advertising (Google AdMob)

The free version shows a banner and, occasionally, a full-screen ad served by Google AdMob (Google Ireland Limited, Gordon House, Barrow Street, Dublin 4, Ireland, and Google LLC). To show and measure ads, the Google Mobile Ads SDK collects your IP address (from which Google derives a coarse location), the device model and iOS version, the app version and language, ad impressions and taps, and, only if you allow tracking, the advertising identifier (IDFA) of your device.

Your choices:

In the European Economic Area, the United Kingdom, Switzerland, and US states with a privacy law, the app shows Google's consent form before the first ad where Google requires it. You can decline personalized ads there and change your choice at any time under More › Privacy options. Without consent, ads are non-personalized.
On every device iOS asks, after the consent form, whether the app may track you (App Tracking Transparency). If you choose "Ask App Not to Track", the advertising identifier is not read and ads are non-personalized. You can change this under Settings › Privacy & Security › Tracking.
System Guard Pro (section 11) removes all ads, and the Google Mobile Ads SDK is not started.

Google processes this data under its own responsibility as well. How Google uses data from apps that use its services: https://policies.google.com/technologies/partner-sites. Google's privacy policy: https://policies.google.com/privacy. The advertising partners Google may share data with when you consent: https://support.google.com/admob/answer/9012903. Google's ad settings: https://adssettings.google.com.

How often a full-screen ad may appear is set by three numbers that the app fetches from Google Firebase Remote Config (section 10); no data about you is sent to fetch them beyond what Firebase collects in general.

10. Usage statistics and crash reports (Google Firebase)

The app uses Google Firebase (the same Google companies as above) for three things:

Firebase Analytics counts how the app is used: which tab was opened, that an explanation, the report, or Compare was opened, that a check-up test or a speed test was run, that a Control Center control or the local network search was used, that the paywall was shown, that a purchase or restore happened, and the ad and consent events. The events carry fixed labels only, never a value read from your device: no addresses, no figures, no names. Firebase adds a random app-instance identifier (reset when you reinstall), the device model, iOS version, app version, language, and the country derived from the IP address, records whether you own Pro, and records the Pro purchase as an anonymous purchase event. We use the statistics to see which features matter and to find problems. Google keeps the event data for up to 14 months.
Firebase Crashlytics receives a report when the app crashes: the stack trace, the device model, iOS version, app version, free memory and storage at the time, and a random installation identifier. We use it to fix crashes. Reports are kept by Google for 90 days.
Firebase Remote Config fetches the three numbers that pace full-screen ads. It sends the app-instance identifier, app version, and language.

The widgets, the share extension, and the Apple Watch app contain no analytics. Firebase's data handling: https://firebase.google.com/support/privacy. Analytics and Crashlytics are switched off in the builds we run during development.

11. System Guard Pro

The purchase is made through Apple's App Store. We receive no name, address, or payment details; Apple's StoreKit tells the app only that the purchase exists. Whether you own Pro is stored on the device (and in the container shared with the widgets and Shortcuts) so that it works offline; Apple's Family Sharing extends it to your family. Restoring uses Apple's servers only.

With Pro you can export the device report as PDF, text, or JSON through the share sheet. Where it goes is your choice; the report contains your device's addresses and model, so share it as you would tell those to someone.

12. Permissions the app asks for

Except for tracking, each permission is asked for the first time you use the feature that needs it, never at launch:

Location (while using): when you tap "Show network name and access point", or run the compass or GPS test. iOS reveals the Wi-Fi name only to apps with this permission. The GPS test shows your position coarsely on screen and discards it. Your position is never sent anywhere.
Local network: when you start Local network (section 5).
Notifications: when you switch on an alert (section 3).
Camera: the camera test shows a live preview from each lens. No photo is taken.
Microphone: the microphone test shows a level meter. Nothing is recorded.
Bluetooth: the Bluetooth test asks whether the radio is on. Nothing is searched for or connected.
Motion & Fitness: the motion sensor test shows live readings, which are discarded.
Face ID: the biometrics test asks for one authentication. The app only learns yes or no.
Tracking: once, after the consent form, for personalized ads (section 9). Declining keeps the app fully usable.
Photos: no permission. When you attach a screenshot to a support message, Apple's picker hands the app only the image you choose.

13. This website and the help pages

The FAQ and the version history in the app open the help pages of this website (https://www.systemguardapp.com/help/). The End-User License Agreement and this policy are shown from the app's own copy. www.systemguardapp.com sets no cookies of its own and has no analytics. The web server keeps a standard access log (IP address, time, requested page, browser) for 14 days, to operate and secure the site. The contact form on the home page embeds Google reCAPTCHA, which loads from Google's servers and, to tell people from bots, sends Google your IP address, browser details, and your interaction with the form; Google's privacy policy and terms apply (https://policies.google.com/privacy, https://policies.google.com/terms). Nothing else on the site, and nothing on the help pages, is loaded from a third party.

14. Legal bases and retention (European Economic Area, United Kingdom)

Personalized advertising and tracking rest on your consent (Art. 6(1)(a) GDPR), given in the consent form and the tracking prompt and withdrawable at any time. Answering your support message rests on the performance of a contract or of steps you asked for (Art. 6(1)(b)). Non-personalized advertising, crash reports, usage statistics without device values, and the server's abuse protection rest on our legitimate interest (Art. 6(1)(f)) in financing, running, and improving a free app securely; you can object (section 15). Retention periods are stated in the sections above; where none is stated, data is not stored by us.

15. Your rights and your choices

Depending on where you live, you have the right to ask us for access to, correction or deletion of your personal data, to restrict or object to its processing, to data portability, and to withdraw a consent at any time with effect for the future. Write to our contact form. In the European Economic Area and the United Kingdom you may also complain to your data protection authority.

Most choices you can make directly: More › Privacy options (consent to personalized ads), Settings › Privacy & Security › Tracking (advertising identifier), the permission switches under Settings › System Guard, Clear results in the check-up, Clear history in History, deleting readings in Battery health, and deleting the app, which removes everything it stored on the device. Because the app has no account and we store no profile, there is usually nothing on our side to delete except a support message; ask and it is gone.

Residents of California and other US states with privacy laws: we do not sell your personal information. Personalized advertising may count as "sharing" or "targeted advertising" under those laws; you can opt out through More › Privacy options and the iOS tracking setting. We do not treat you differently for exercising your rights.

16. Where data is processed

RBT Digital LLC is registered in the United States; the app's server and this website are hosted in Germany, and support mail is read there. Google processes advertising and Firebase data in the European Union, the United States, and other countries where Google operates; for transfers out of the European Economic Area Google relies on the EU-US Data Privacy Framework and the EU standard contractual clauses (https://business.safety.google/privacy/). Cloudflare, for the speed test, serves from the location nearest to you.

17. Children

System Guard is not directed at children. In the European Economic Area we do not knowingly collect personal data from anyone under 16, elsewhere under 13; personalized ads are not shown where the age of consent is not met. If you believe a child has sent us data, write to us and we will delete it.

18. Changes to this policy

We may update this policy when the app or the services it uses change. The new version appears in the app and at https://www.systemguardapp.com/privacypolicy/ with a new "Last updated" date. If a change materially affects how we use your data, we point it out in the app's release notes. This version replaces the one of September 13, 2026, which did not yet describe the local network, the history and its alerts, the traffic figures, or the battery health import. That version replaced the policy of February 4, 2017, which described an earlier generation of the app; that app reported the device's network details to our server, the current app does not, and that server no longer exists.

19. Contact

RBT Digital LLC, 30 N. Gould Street, Ste 6045, Sheridan, WY 82801, United States. E-mail: our contact form.