Sensor Toolkit is a set of five small tools that use sensors your phone already has: a light meter, a sound meter, a compass with a bubble level, a screen ruler and a flashlight with an SOS signal. Everything the sensors read is used on your device to draw the display. None of it is stored, and none of it is sent anywhere.
Last updated: 2026-10-14
The app does not use your location (the compass reads the magnetometer, not GPS), your contacts, your files or your camera image.
The sound meter listens only while a measurement is running, that is between your tap on Start and your tap on Stop, and it stops when you leave the tool or the app. The sound is measured, not recorded: the app computes a level from each short buffer and discards the buffer. If you refuse the microphone, the other four tools work as before.
The app itself collects nothing about you. It has no account, no sign-in and no analytics of its own. Because it is free and ad-supported, the Google AdMob advertising SDK collects a limited set of data to serve ads (see Advertising below).
This app shows one banner ad at the bottom of the screen, through Google AdMob. It shows no full-screen ads. To serve and measure ads, the AdMob SDK collects and shares the following data with Google — even though the app itself never requests it:
This data is used for advertising, analytics, and fraud prevention, and is sent over an encrypted (HTTPS) connection. See Google's disclosure at support.google.com/admob/answer/6128543. No sensor reading and no sound is part of it.
You can reset or delete your advertising ID at any time in your device settings (Settings → Google → Ads).
In the European Economic Area, the United Kingdom and Switzerland the app asks for your consent before any ad is requested, using Google's consent form (User Messaging Platform), and no ad is requested while that question is open. There you decide whether ads may be personalised. Where you were asked, the menu on the start page contains Privacy options, which lets you change your choice at any time. After you have bought Remove Ads, that entry is not shown.
The app offers one optional one-time Remove Ads purchase, on the start page and in its menu. There is no subscription and no recurring charge. The purchase is processed entirely by Google Play Billing — we never see or store your payment details. The app keeps only a yes/no note on the device that ads were removed. Once the purchase is recorded, the app requests no further ads; from the next start it does not start the advertising software and does not ask for ad consent. The app checks with Google Play for an earlier purchase at every start, so a purchase is restored automatically, for example after you reinstall the app.
The app stores a few settings on your device using Android's SharedPreferences: your theme choice (light / dark / system), the ISO value of the light meter, the unit and calibration of the ruler, the last view of the compass tool, the brightness of the flashlight, and whether Remove Ads was purchased. This data stays on your device and is removed when you uninstall the app.
The five tools need no internet connection. Network access is used only to request ads, to load the consent form where one applies, and for Google Play (the Remove Ads purchase, and restoring it).
The start page and its menu contain More apps, a list of other apps from the same studio. The list and the app icons are part of the app; nothing is loaded from the internet to show them. Tapping an app opens its page in the Google Play Store app (or in your browser, if the Play Store app is not available). The app sends nothing when you do this; what Google Play records is covered by Google's own privacy policy.
The menu on the start page contains Send feedback. It opens a pre-filled draft in your own email app, addressed to feedback+sensor_toolkit@99ersstudio.com, with the app name and version and your device's operating-system version included so we can reproduce issues. Nothing is sent automatically: an email goes out only if you send it, and you can edit or delete any part of the draft first.
The readings are for guidance only. Phone sensors are not calibrated instruments and vary between devices. The sound meter shows an approximate level and must not be used to judge hearing safety. The compass is affected by metal and magnets nearby. The SOS function is a light signal only; it does not contact emergency services or anyone else.
This app is not directed at children under 13. We do not knowingly collect data from children.
If we update this policy, we will publish the revised version at this URL and change the date at the top. Continued use of the app after changes constitutes acceptance.
Questions about the app: support@99ersstudio.com. Requests about your personal data: admin@99ersstudio.com (see Your Rights below).
The controller responsible for data processing in connection with this app is 99ersstudio, LLC (Delaware, USA), represented by Aaron Philipp Vogelsang, 131 Continental Dr, Suite 305, Newark, DE 19713, USA. Contact: admin@99ersstudio.com. (US company — no VAT ID / no EU VAT registration.)
99ersstudio, LLC is established outside the European Union. As our representative in the Union pursuant to Article 27 GDPR we have appointed Prighter EU Rep GmbH, Schellinggasse 3/10, 1010 Vienna, Austria. Data subjects in the EU/EEA may exercise their data protection rights through our representative — online contact: https://app.prighter.com/portal/15694257215.
If you are located in the EU/EEA, you have the rights granted under Articles 15 to 22 GDPR, including access, rectification, erasure, restriction, data portability and objection. You can exercise these rights by emailing admin@99ersstudio.com — or conveniently via our Trust Center: https://app.prighter.com/portal/15694257215.