Install Mobile on the Fly: Android

The Mobile on the Fly app automatically sends the photos and videos from the phone or tablet to the computer or NAS at home, as soon as the device is on the Wi-Fi. Allow 5 minutes. Mobile on the Fly must first be installed on the computer or the NAS (guides).

1. Before you start

Android 8 or later (Settings › About phone › Software information › Android version).
Mobile on the Fly installed on the computer or the NAS, with its pairing page at hand (it shows the QR code to scan).
The phone on the home Wi-Fi, the same network as the computer.

The app is not on the Play Store: it is downloaded from our site, and Android asks for permission the first time. This is expected, and it then updates itself.

2. Install the app

On the phone, open the download link:
- either scan, with the phone's camera, the small QR code on the "No app on the device yet?" card, on the computer's pairing page;
- or type the address https://mobileonthefly.com/download in the phone's browser, then Download next to Android app.
The browser may warn that "this type of file can harm your device": tap Download anyway.
Open the downloaded PhotoRelay.apk file (download notification, or the My Files app › Downloads).
Android says the browser is not allowed to install unknown apps: tap Settings, turn on Allow from this source, then go back (back arrow).
Tap Install. If Google Play Protect says it doesn't recognize the app: More details › Install anyway (if you are offered to send the app for scanning, you don't need to).
Tap Open.

On first launch, Mobile on the Fly asks for access to photos and videos and for permission to show notifications: tap Allow ("Allow all" for the photos, if Android offers "Allow limited access": otherwise only the selected photos will be sent). Nothing is deleted or sent anywhere other than your computer.

3. Link the phone (pairing)

On the computer or the NAS, show the pairing page: Mobile on the Fly icon › Pair a device… (Windows), or the Pair a device button at the top of the settings.
In the app, tap Scan the QR code and allow the camera.
Check the Name of this device field: it is the name of the folder for its photos on the computer (for example "Julie's phone"). Change it if needed.
Point at the QR code shown on the computer screen.
The app shows "Paired with “COMPUTER-NAME”. Photos are sent as soon as the device is on the home Wi-Fi."

4. Let Mobile on the Fly work in the background

For photos to be sent without opening the app, Android must let Mobile on the Fly run in the background. If the "So that photos are sent on their own…" card appears:

Tap Allow in the background, then Allow in the Android window.
If the card is still shown: tap Or: Battery › Unrestricted and choose Unrestricted (Samsung: Battery › Unrestricted; Xiaomi: Battery saver › No restrictions and turn on Autostart; Huawei: App launch › Manage manually, turn everything on).

For Mobile on the Fly to update itself, also tap Allow updates if the card appears, and turn on the permission to install apps.

5. Check that everything works

Take a photo, with the phone on the home Wi-Fi.
In the app, tap Send now: To send goes down, Delivered goes up.
On the computer, the photo is in the Mobile on the Fly\<device name>\Camera\… folder; earlier installations: PhotoRelay folder.

After that, everything happens on its own: as soon as you are back home, after each new photo, and every 15 minutes.

6. The app screen

Computer: the paired computer or NAS.
To send / Delivered: photos waiting and photos that have arrived. Refused by the computer: see the history.
Send now: sends right away. Pair with another computer: switch to another computer (new PC, NAS…).
Cloud relay (paid plan): away from home, photos go through an encrypted relay. It is turned on in the computer's settings; the phone gets it by itself when it is back home. The Use mobile data (4G) switch is off by default: away from home, photos wait for a Wi-Fi.
Send history: what happened in the background, with any error messages.
Language: automatic, French, English, German, Italian or Spanish.

7. Common problems and solutions

"computer not found (turned off, or not on the same Wi-Fi)"

Is the computer on? The photos will be sent later: nothing is lost.
Is the phone on the home Wi-Fi, not the guest Wi-Fi or mobile data?
Is a VPN or a blocking "Private DNS" active on the phone? Turn it off to try.
On the computer: see the "computer not found" section of its guide (Private network on Windows, firewall).

"QR code expired or already used: show a new one on the computer"

On the computer, click New QR code, then scan again.

"the computer answering is not the one from the QR code: pairing refused"

Another device is answering at the computer's address (computer replaced, unusual network). Show a new QR code on the right computer and start again; if the message comes back, contact support.

"this device is no longer authorized by the computer: pair it again"

The phone was removed in the computer's settings, or Mobile on the Fly was reinstalled without a recovery key. Tap Pair with another computer and scan a new QR code.

"the computer's photo folder is unavailable (disk unplugged?)" or "not enough space left"

The problem is on the computer: plug the disk back in, or free up space. Nothing is lost: the phone keeps the photos and tries again.

"Without the camera, the QR code can't be read."

Android Settings › Apps › Mobile on the Fly › Permissions › Camera: Allow.

Photos are only sent when I open the app

See step 4: allow Mobile on the Fly in the background (battery "Unrestricted").

Only some photos are sent

Access to photos is limited: Android Settings › Apps › Mobile on the Fly › Permissions › Photos and videos › Always allow all.

"App not installed"

An old version installed from another source is preventing the installation: uninstall it, then reinstall from our site. Also check that there is space left on the phone.

8. Updates

The app checks for new versions at launch and then every hour, and installs them by itself (Android 12 and later); on older versions, a "Mobile on the Fly: update ready" notification asks you to tap to install. The version is at the bottom of the app screen.

9. Uninstall

Long-press the Mobile on the Fly icon › Uninstall. The photos on the phone are not touched, nor those already stored on the computer. Remember to remove the device in the computer's settings (Devices tab › Remove).

10. Still stuck? Contact support

Write to support@unveiltech.com and include:

the phone model and its Android version;
the app version (at the bottom of its screen);
the system of the computer or NAS;
a screenshot of the app with the send history open.