Last updated: 9 September 2026
Inertial is an Android application for pilots of light aircraft that records a flight and reconstructs its track. This policy describes what the application does with information. It is short because the application does very little with it.
This is an early version, and it uploads your flight recordings to us. They are sent so that we can run our estimation algorithms against real flights and improve the track the app reconstructs across a satellite outage. That is the only thing they are used for. There is no account, no sign-in, no analytics, no advertising, and no third-party software development kit that reports on your use of the app.
The map also downloads its imagery from a map provider as you use it, the way any map does.
If you would rather not send recordings, there is no switch in the application today, and the only way to stop it is to keep the phone off the network — flight mode, or no signal. A switch that genuinely stops all uploading is being built and will arrive in a coming update. Until it does, saying so here is better than leaving you to discover it.
Your device's location, from its satellite receiver: position, altitude, speed and direction of travel. Inertial reads this while the application is open in front of you, so that the moving map can show where you are, and for the length of a recording, where it is the flight track. It is not read when the application is in the background and no recording is running.
Your device's motion sensors — the accelerometer, the gyroscope, the magnetometer, and the barometric pressure sensor where the device has one — are read only while a recording is running. These are what allow the application to continue estimating position when the satellite signal is unavailable.
Your device's cameras, only if you switch one on. Inertial can save still images during a recording, at about one a second, from either of the phone's two cameras. Both are off when you install the application, each is switched on separately, and switching one on shows a warning first. They are read only while a recording is running.
These images are what a later version can use to see what the lens saw, alongside the motion sensors. Depending on how the phone is mounted, a camera may be pointed at the sky, at the ground, or into the cockpit — the application cannot know which. If a lens can see the cockpit it will photograph whoever is in it, for the whole flight, including passengers. Ask them first.
Camera images never leave your phone. They are not uploaded with the recording, and the server refuses them. They are deleted when you delete the recording, and when you uninstall the application.
Recording starts only when you start it, and stops when you stop it. While a recording is running, the application displays an ongoing notification carrying a control that stops the recording immediately, so that a recording can never be running without your knowing. On Android 14 and later the system may allow you to swipe that notification away; the recording is then still listed in Android's own active-apps indicator, and the notification returns the next time its state changes. It is never removed by the application while a recording is running.
To your phone's own storage, and to us.
Every recording is written first to the application's private storage on your phone.
It does not stay there. Recordings are sent to storage we operate on Cloudflare, in chunks while the recording is still running, so that a flight is not lost if the phone dies at the end of it. That means the current flight is being transmitted while you are flying it, whenever the phone has a working connection, and not only after you land.
An earlier version of this page said uploading was "being added and is not in the version you are running". That was true when it was written and had stopped being true before this sentence replaced it. The application in your hands uploads. We would rather correct it in plain words than quietly.
Why. Inertial estimates where you were when the satellites stopped answering. Making that estimate better needs real recordings of real flights: the phone's own motion sensors, the satellite fixes it did get, and the stretches where it got none. We run our algorithms against those recordings afterwards and use what we learn to improve the track the app reconstructs. There is no other purpose, and the recordings are not sold, shared or used for advertising.
What is in a recording. Where you flew and when, at up to several hundred samples a second, together with the phone's motion-sensor and barometer readings and the identity of the phone model. That is location data about you, and we are not going to describe it as anything else.
The map. The moving map downloads its background imagery from a map provider as you pan and zoom. Those requests contain the map square being drawn and nothing else — no position of yours, no recording, no identifier. Map imagery is cached on your phone so that it keeps working with no signal.
You can also export a recording using Android's share sheet. When you do that, you are handing a file to an application you have chosen. What that application then does with it is governed by its own policy, not this one.
On your phone: until you delete it. You can delete an individual recording inside the application, and uninstalling removes all of them.
With us: for as long as it is useful for improving the estimate, which for this early version means indefinitely. Uninstalling the application does not delete what has already been uploaded. Ask us at the address below and we will delete your recordings.
| Permission | Why the application asks for it |
|---|---|
| Location (precise) | To record the flight track and to correct the inertial estimate. |
| Foreground service, location type | So that recording continues while the screen is off, for the length of a flight. |
| Notifications | To show the ongoing notice that a recording is running, with its stop control. |
| High sampling rate sensors | Android requires this to read motion sensors at the rate the estimator needs. |
| Camera | To save still images during a recording, if you have switched a camera on. Both are off until you do. |
| Foreground service, camera type | So that a camera you switched on keeps saving images while the screen is off. |
Inertial does not request background location access, and does not hold it: the moving map reads your position only while the application is in front of you, and a recording holds it only while the ongoing notification is visible. Nothing is written to a recording unless you have started one.
The camera permission is requested only when you switch a camera on, and the cameras are used only while a recording is running. No picture is taken outside a recording you started, and there is no way to use Inertial as a camera.
While a recording is running, the small thumbnail on the flight screen shows a live view from the lens, so that you can see what is being saved. Underneath it is the last image that actually reached the phone's storage, which is what you see if the phone will not run a live view alongside the saving. Before you start, and after you stop, the lens is closed and the thumbnail shows only the last image the previous recording saved.
Inertial is intended for licenced pilots and is not directed at children.
Inertial is sold through Google Play as a one-time purchase. Your payment is handled entirely by Google; we never see your payment details. Google's own privacy policy governs that transaction.
If this policy changes, the date at the top changes with it, and the previous version stays available at this address's history.
Questions about this policy, or about the application: support@flyinertial.com
This policy is published at https://flyinertial.com/privacy/.