Almost every ADS-B problem falls into one of five symptoms. Find yours below. Everything starts from Menu › Setup › ADS-B, the ADS-B Status window, which tells you what iFly is hearing.

First, check the basics

1. The receiver is switched on, charged and within a few feet of the tablet.
2. The tablet is connected to the receiver: on its Wi-Fi network (named something like Stratus_xxxx, Levil_xxxx or stratux) or paired in Bluetooth settings, depending on the receiver.
3. In iFly, Menu › Setup › ADS-B › Options › Change Selected Device is set to Auto Detect.
4. No other EFB or ADS-B app is running on this tablet or any other device. A receiver feeds one app at a time.
5. The app has permission to talk to the receiver: iOS Settings › Apps › iFly EFB › Local Network on; Android Settings › Apps › iFly EFB › Permissions › Nearby devices allowed (Bluetooth receivers) and Location allowed.

"No Heartbeat": iFly does not see the receiver

• Confirm the tablet really joined the receiver's Wi-Fi. Phones and tablets often drop a network that has no internet and fall back to cellular. On Android, when the "no internet" prompt appears choose to stay connected, or turn on Airplane Mode first and then re-enable Wi-Fi so there is nothing to fall back to.
• Battery receivers switch themselves off after a period of inactivity. Check its lights.
• Turn off any VPN, proxy or third-party antivirus/firewall on the tablet. These commonly block the local broadcast.
• Choose Options › Reset / Reconnect in the ADS-B window, then wait a minute.
• If Auto Detect never finds it, choose Options › Change Selected Device and pick the receiver's brand explicitly, then restart iFly.
• Stratus 3 that was last used with ForeFlight: ForeFlight puts it in a locked mode. Install Appareo's free Stratus Horizon Pro app, connect, open Settings and turn on Open ADS-B Mode. See Connect a Stratus to iFly.
• Bluetooth receivers on Android (Dual XGPS170 and similar): the tablet can be paired yet iFly receives nothing until the Nearby devices permission is granted. Settings › Apps › iFly EFB › Permissions › Nearby devices › Allow, then Reset / Reconnect.
• uAvionix echo or ping on an iFly 740b that works fine with a phone: remove the SD card, factory-reset the 740b, reinsert the card and connect again.

Connected, but "Out of Range" or "Tower Idle"

The receiver is talking to iFly but hears no ground station. This is normal on the ground and at low altitude: weather, NOTAMs and TIS-B traffic come from FAA ground towers, and you generally need to be airborne (the FAA quotes roughly 800 ft AGL) with line of sight to one. Direct air-to-air traffic still arrives on the ground. Tower Idle means data was arriving and has paused for over a minute, typically behind terrain or during descent; after a few minutes it becomes Out of Range. See ADS-B Status states.

Traffic, but no weather

• Traffic and weather travel on separate bands and are separate systems inside the receiver. Some receivers are traffic-only; the uAvionix pingUSB is the common example. Check the spec sheet.
• Weather only comes from ground towers, so you need to be airborne and in coverage (see above). Traffic can arrive on the ground from nearby aircraft.
• Check the receiver's antenna is installed and not damaged; an echoUAT with a loose antenna is a known case.

Everything worked until another app was opened

A receiver sends one kind of data stream at a time, and iFly and ForeFlight use different ones. If ForeFlight (or any other EFB) connects, on this device or another, iFly stops receiving. Close the other app or disconnect the other device, then in iFly choose Menu › Setup › ADS-B › Options › Reset / Reconnect, which switches the receiver back to the format iFly reads.

Receiver-specific notes

• Stratux: if the status lights do not come on or Wi-Fi never appears, the microSD card is usually full or corrupt. Reflash it (see Reflash a Stratux SD card) or replace it. Its AHRS needs a GPS lock before it works.
• uAvionix echoUAT: the Wi-Fi module can fail and stop responding; uAvionix sells a replacement part.
• Garmin, Sentry, Stratus 2: not compatible with iFly at all. See Supported ADS-B receivers.

Is data actually arriving?

In the ADS-B Status window the counters next to Heartbeats, traffic and weather messages should tick upward. If they stay at zero the tablet is connected to the receiver but not receiving its data, which points at permissions, another app holding the stream, or a VPN. Options › Show Detailed Form opens Connected Devices, where a working receiver appears by name.