FreeFCC is an open-source iOS app that switches a DJI RC-N1, RC-N2 or RC-N3 from CE to FCC radio power over the same cable you already use for DJI Fly. No jailbreak, no PC, no server, no account, no UDID. Confirmed on real hardware with an RC-N3 and a DJI Neo.
linked aircraft 1581F87L…
the real app, v1.4
Same controller, same aircraft, a different country code. CE is the European region and it caps the radio. FCC is the US region and it lets the radio run at the power DJI designed it for. The numbers below are DJI's own limits for the RC-N3.
Reaching FCC is a single WiFi Set Country Code frame with US in it, delivered to the right component inside a service-mode window. Finding that out on real hardware is what this project is.
DJI's published limits for the RC-N3 (2.4 GHz: 33 dBm FCC, 20 dBm CE; 5.8 GHz: 33 dBm FCC, 14 dBm CE). Illustration, not a live measurement.
An RC-N3 cabled to an iPhone, a DJI Neo in the air, and the DJI Fly Transmission graph showing FCC power with the signal reaching well past the 1 km reference. Three things had to be right, and finding them was the work.
DJI Fly, Transmission tab. 2.4 GHz spectrum recorded with FCC power active on an RC-N3 and a DJI Neo, straight from the phone that ran the unlock.
FreeFCC
com.dji.logiclinkOne of the two MFi protocol strings DJI does not publish. A build declaring only the three documented strings never sees the controller, because iOS hides an accessory whose protocols you did not declare. The string was read off the hardware.
USThe command is the WiFi Set Country Code the controller already accepts. The country it carries is what decides CE or FCC. Everything else in the sequence exists to deliver that frame to the right component, inside the right window.
Not just powered on. The frames reach the controller and stop there until it is relaying to a drone. The app shows a green link line with the aircraft serial once the drone is there.
Every capability below is either confirmed on hardware or marked as work in progress. Nothing here is a promise.
max_height = 500 and the flight controller acknowledges it, but the aircraft reads back 120 m, so the ceiling is enforced drone-side. The parameter that lifts it is being reverse engineered in the open.Paid FCC mods have existed for years, and they work. What they charge for is a licence tied to your device or your drone, renewed every year, for a closed app you cannot inspect. On Android, free open-source FCC apps for the RC-N1 have been around for a while. On iPhone there was nothing free until now.
| Criterion | FreeFCCthis project, open source | Drone-TweaksFCC mod for DJI Fly for iOS | Drone-HacksWindows app, per-aircraft mods |
|---|---|---|---|
| Price | Free, GPL-3.0. Nothing to buy, ever. | €39.99 per iOS device, €65.99 for iPhone and iPad, €49.99 for the RC 2 or RC Pro version. | Paid licence per aircraft, priced by model on drone-hacks.com. |
| Licence | None. Build it once with a free Apple ID. | One device, signed to your UDID, about 12 months of updates, then renew. | Per drone, tied to that aircraft. |
| Where it runs | On the iPhone, over the MFi cable. No PC. | On the iPhone or iPad, as a separate signed app. | On a Windows PC with the drone cabled over USB. |
| Source code | Open. Every frame is a JSON profile you can read before it is sent. | Closed. | Closed. |
| Server, account, tracking | None. The app has no network access. | Licence delivery and renewal through the vendor. | Licence activation through the vendor. |
| Controllers | RC-N1, RC-N2, RC-N3. Screen controllers are out of scope. | Standard controllers, plus DJI RC, RC 2 and RC Pro with the dedicated versions. | Works on the aircraft itself, plus RC Pro. |
| Beyond FCC | 500 m altitude and Sport speed are open issues, worked on in public. | FCC, plus AirSense on the Mavic Air 2 version. | FCC, no-fly-zone removal, altitude limit, acceleration. |
| Install effort | A Mac with Xcode once, then Run. Not a tap-to-install. | Send your UDID, tap the link, install. | Windows PC, USB cable, patch the aircraft. |
| Confirmed hardware | RC-N3 + DJI Neo confirmed. Other pairs: testers wanted. | 25+ aircraft listed, Neo, Neo 2, Mini 5 Pro and Lito included. | Mini 4 Pro, Mini 3 Pro, Air 3, Mavic 3, Neo among others. |
Drone-Tweaks prices and terms as listed on drone-tweaks.com on 6 September 2026. Drone-Hacks details from drone-hacks.com and its public wiki on the same date. Both are third-party products, not tested by this project, and their lists change with DJI firmware.
Connect, enable, read the log, inspect the profile. The app is built to be understood, not just used.
Works with DJI RC-N series controllers
FreeFCC talks to the controller, and the controller relays to whatever aircraft it is linked to. So compatibility has two halves: the controller must be an RC-N model with a phone cradle, and the aircraft must be one DJI pairs with that controller. FCC mode on a DJI Neo, Neo 2, Flip, Mini 4 Pro, Mini 5 Pro, Air 3 or Air 3S goes through the same RC-N3 and the same frames.
Confirmed on hardware with DJI Neo
DJI NeoFCC confirmed
DJI Neo 2testers wanted
DJI Fliptesters wanted
DJI Mini 5 Protesters wanted
DJI Mini 4 Protesters wanted
DJI Air 3Stesters wanted
DJI Air 3testers wantedEverything DJI lists for the RC-N3: Neo, Neo 2, Flip, Mini 5 Pro, Mini 4 Pro, Air 3S, Air 3, Avata 360, Lito 1, Lito X1.
Same protocol, testers wanted
DJI Air 3testers wantedDJI Air 3Stesters wantedDJI Mini 4 Protesters wantedDJI Neotesters wantedDJI Fliptesters wantedEverything DJI lists for the RC-N2: Air 3, Air 3S, Mini 4 Pro, Neo, Flip.
Same protocol, testers wanted
DJI Mini 3testers wanted
DJI Mini 2 SEtesters wanted
DJI Mavic 3 Protesters wantedEverything DJI lists for the RC-N1: Mavic Air 2, Air 2S, Mini 2, Mini 2 SE, Mini 3, Mini 3 Pro, Mavic 3, Mavic 3 Classic, Mavic 3 Pro, Mavic 3 Cine.
Aircraft lists follow DJI's published compatibility for each controller as of September 2026, and DJI extends them with firmware updates. "Compatible" here means the controller pairs with that aircraft. FCC power through FreeFCC is confirmed only where marked, and every other pair is exactly what the project is asking testers to try, no coding needed, just the app and a log.
The controller relays commands to the aircraft only after DJI Fly has woken that link, and the link stays warm for a while after DJI Fly closes. That warm window is what the app needs.
profile@02/RCLink: 38 responses means the aircraft answered.The app opens an ExternalAccessory session on the controller's MFi protocol and speaks DUML over the stream, the same command protocol DJI Fly uses. Knowing where each link sits is knowing where an apply can fail.
Builds each DUML frame with its CRC-8 and CRC-16, wraps it in the link envelope, keeps the session alive with a keepalive.
Opens an EASession on com.dji.logiclink. The bottom port is charging only and carries no data channel.
Handles the radio and WiFi frames itself. Country code US inside one service-mode window moves the region to FCC.
Relays flight-controller frames to the aircraft only while the drone is linked. This is where a silent apply is born.
Owns the flight-controller parameters, altitude and speed among them, and streams telemetry back, serial number included. Seeing the serial means the chain is complete.
The FCC profile is a JSON file in the app bundle. The whole burst has to land inside the service-mode window that the first frame opens and the last one closes: 30 ms per frame puts a two-round pass at about 1.5 seconds. Stretch it past a few seconds and the radio silently stays on CE.
Each apply sweeps several sender and framing combinations and counts the responses, so the log names the path your hardware answered on. A one-frame CE restore profile puts the radio back to its factory region.
The full walkthrough, protocol and frames, transport, the service-mode window, the sweep and every hardware finding, is in the technical documentation on GitHub, in English, with an Italian version alongside it.
// fcc.json, excerpt. s = sender, i = command id, d = destination, p = payload { "s": 16, "i": 88, "d": 18, "p": "030100", AUTOTEST enter service mode } { "s": 6, "i": 114, "d": 6, "p": "00000000000100", RADIO set region param, FCC } { "s": 3, "i": 249, "d": 3, "p": "8a237103f401", FLYC max_height = 500 (0x01F4) } { "s": 7, "i": 48, "d": 9, "p": "55530000555300000100", WIFI country code US, 2.4 GHz } { "s": 7, "i": 48, "d": 9, "p": "55530000555300000100", WIFI country code US, 5.8 GHz } { "s": 6, "i": 114, "d": 6, "p": "000000000001ff", RADIO commit region change } { "s": 16, "i": 88, "d": 18, "p": "030100", AUTOTEST exit service mode } // 22 frames in total, 2 rounds, 30 ms between frames, re-applied every 4 s while holding
This is a sideload for your own hardware, not an App Store build: it opens DJI's MFi protocol strings and changes a regulatory radio setting, two things a store build could never ship.
Generate the project, open it, pick your iPhone as the destination and press Run. The project signs with the team wildcard profile, so there is no App Store Connect setup. The first launch on a free account needs the developer profile trusted once in Settings, then it just works.
Open the repository# clone git clone https://github.com/andreapianidev/DJI-FCC-Unlock-iOS.git cd DJI-FCC-Unlock-iOS # generate the Xcode project (once) brew install xcodegen xcodegen generate # open, pick your iPhone, Run open FreeFCC.xcodeproj
FCC power is done and confirmed. The rest is open reverse engineering, and it moves faster with more hands and more hardware. Each issue lists what is known, the exact parameter hashes and commands, and the next concrete step.
The headline feature. The aircraft acknowledges the write but keeps enforcing 120 m, so the governing parameter is still to be found.
Drone-side reverse engineering, staged as an attitude-range and vertical-velocity boost, written as 32-bit floats in v1.4.
The tool that unblocks both of the above: reading parameters back instead of writing blind.
Initialise the controller-to-aircraft link from the app itself, so the warm window is no longer needed.
Run the app on your hardware and post the log. Findings from real devices are as valuable as code.
For a real in-app CE/FCC indicator instead of trusting the DJI Fly graph.
Star the repository, pick an issue, or just run it and post your log. The project is GPL-3.0, so every improvement stays free for everyone.
andreapianidev/DJI-FCC-Unlock-iOSCE is the European radio region: DJI caps the 2.4 GHz link at 20 dBm EIRP, about 100 mW, and 5.8 GHz at 14 dBm. FCC is the US region: 33 dBm on both bands, about 2 W, with more channels available. Same controller, same aircraft, a different country code. In free space 13 dB of extra power is roughly 4.5 times the distance at the same signal quality.
Yes, this one. FreeFCC is a free, GPL-3.0 open-source FCC unlock that runs natively on iPhone with an RC-N1, RC-N2 or RC-N3 controller. Drone-Tweaks sells its FCC mod for DJI Fly on iOS for €39.99 per device, signed to your UDID, with updates for about 12 months. FreeFCC has no licence, no UDID registration and no renewal: you build it once in Xcode with a free Apple ID.
FreeFCC changes the region on the controller, so it applies to every aircraft the RC-N controller is linked to. FCC power is confirmed on hardware with an RC-N3 and a DJI Neo. The Neo 2, Flip, Mini 4 Pro, Mini 5 Pro, Air 3 and Air 3S pair with the same controller and are expected to behave the same, and the project is collecting logs from testers to mark each one confirmed.
That depends on your country. In the EU and most CE regions the legal ceiling on 2.4 GHz is 20 dBm EIRP, and FCC mode transmits above it. Using it may require authorisation from your regulator or may simply not be allowed. FreeFCC is published for education and research; you are responsible for complying with local law. If you are not sure whether this is legal where you live, do not use it.
No jailbreak. FreeFCC talks to the controller over the same MFi accessory channel DJI Fly uses, from a normal iPhone. You need a Mac with Xcode once, to build the app with a free Apple ID and put it on your phone. After that nothing else is required and nothing runs on a server.
The phone-cradle controllers: DJI RC-N1, RC-N2 and RC-N3. FCC power is confirmed on hardware with an RC-N3 and a DJI Neo. RC-N1 and RC-N2 use the same MFi link and the same DUML commands, and the project is collecting test logs for them. Screen controllers such as DJI RC, RC 2 and RC Pro have no phone cable and are out of scope.
Not by itself. DJI Fly renegotiates the region when it connects and the radio falls back to CE. FreeFCC re-applies FCC on an interval while it holds the link in the background, and the power-cycle sequence in the Using it section keeps FCC in place when DJI Fly reopens, confirmed on hardware.
Not yet. The app writes max_height = 500 and the flight controller acknowledges it, but reading the value back the aircraft still reports 120 m, so the 120 m ceiling is enforced on the drone, not only inside DJI Fly. The parameter that governs a real 500 m unlock is still being reverse engineered in the open, issue #1 on GitHub. FCC power is a separate mechanism and works.
No. It has no server, no account, no analytics and no network access. Every byte it sends to the controller is a plain JSON profile you can read inside the app, and the activity log stays on your phone until you decide to share it.
It may. Changing a regulatory radio setting can void your warranty and DJI Care Refresh coverage. FreeFCC ships a CE restore profile that puts the radio back to its factory region with one tap, and FCC itself lives in RAM, so a full power cycle without the app returns the controller to CE.
FreeFCC is published for educational and research purposes. Modifying radio transmission power or altitude limits may violate the law where you are. In most places, transmitting above the power permitted for your region, or flying above the permitted altitude, requires authorisation from the regulator. You are solely responsible for compliance. If you are not sure whether this is legal where you live, do not use it.
This project is not affiliated with, endorsed by, or sponsored by DJI, Drone-Tweaks or Drone-Hacks. Using it may void your warranty and DJI Care Refresh coverage. "DJI", "DJI Fly", "RC-N1", "RC-N2", "RC-N3" and the aircraft names on this page are trademarks of SZ DJI Technology Co., Ltd., used only to describe compatibility. Product images are DJI's own renders, shown for the same purpose. Drone-Tweaks and Drone-Hacks are named only for comparison, with their public prices and terms.