Let us identify. Let us fix. Let Us Drone.

Patience is a virtue. At least that is what I tell myself when I'm out flying and there is so much lag in the video transmission that I want to see just how far an iPhone can be thrown if a perfect wind-up is executed.

When I sat down to write this post, I thought that I'd be able to provide a short but thorough guide to eliminating that ever so annoying video lag. What transpired over the next 16 hours turned out to be a writing marathon (okay, so I had a break…or four). The end result is a list of 28 reasons why you may be experiencing video lag with the DJI GO 4 app and how to fix it.

Hey DJI, I love what you're doing, but the fact that this post is 2,603 words means that I have undeniably identified an area that “needs improvement”. If you don't have any idea what's causing the video lag, grab your reading glasses and kick that dog off your comfortable chair.

What exactly is happening when the image gets all screwed up?

Latency: the discrepancy between the time delay of stimulus and response in the simulation as compared to the real-world equivalent.

The signs come in various forms, such as the video being blurry, laggy, or choppy. Maybe the image is freezing or the app is crashing! What about the dreaded green/purple/black lines? The device that you are using to fly the drone is essentially not able to process the incoming video quickly enough to display it on your screen. I think it would be safe to say that 99% of people who have piloted a DJI drone have experienced at least one, if not all of the aforementioned side-effects.

Is your phone or tablet compatible?

Ah, the first question you're likely to hear if you ask DJI directly why you're having so many problems with the video transmission: “is the device you're using on the supported device list?” If the answer is no, that does not necessarily mean that your phone or tablet will not be able to fly the drone. DJI just has a list of devices that they have tested with their drones, and can, therefore, confirm their compatibility. However, using one of these approved devices will inevitably help your odds of seeing a clear video.

When downloading the DJI GO or GO 4 app, you can see if your device makes the cut. I have attached a screenshot of what this looks like.

Our friends over at Phantom Help have created a list of the “Best Tablets and Phones for DJI GO (Updated Daily)” so you can see if your device makes the cut. That list can be found here. If you are planning to purchase a new phone or tablet for your drone, I will say that the edge goes to Apple in terms of which devices work better with DJI drones. That is not to say that your brand new Samsung won't work flawlessly with your Mavic, but the larger quantity of complaints come from the Android crowd.

Is your device, RC, AC, and app updated?

Speaking of updates, this is where decisions get tricky. There are four things that get updated on a regular basis.

DJI GO 4 App: As I just mentioned above, the app frequently gets updates. When we think of things getting updated we generally see this as a positive thing as it shows that developers are continually working to improve the functionality of the products. With that being said, if I had a dime for every time I heard someone say “my *insert drone here* worked fine until I updated the app!”, I could probably buy a Spark.

Remember that each app update will require a bit more from your device. Many people have reported that the only difference regarding the quality of the image transmission before and after an app update is which device they are using. DJI will likely make you update the app eventually, but maybe try taming that trigger finger; at least until you see how others are being affected by the latest update.

If you have been having all kinds of video lag since updating the app, it is possible to rollback to the previous version. I can't speak much to this as I have never tried it, but here are YouTube tutorials on how to undertake such a task: click here for Apple, and here for Android. One more thing you can try is deleting and reinstalling the app.

Aircraft & Remote Controller: Similar to the app, the aircraft and remote controller get periodic firmware updates. These are supposed to improve the overall experience of flying. If you're having issues with the video quality and a firmware update is available, then by all means, give the update a shot. Like the app, people often report having issues with the quality of the image after updating. If you recently did a firmware update on the RC and/or the AC and have since been having problems with the image transmission, you may want to rollback the firmware to the previous version.

To check your current firmware or to go back to a previous one, tap and hold the three horizontal lines (the “plus” if you have an iPad) in the top right corner of the DJI GO 4 app for 10 seconds. Release and you'll see a screen with firmware information. You have the option to refresh (reinstall) your current firmware or rollback to a previous one. I'd recommend refreshing before rolling back. This process can also be done with the DJI Assistant 2 on your computer.

Phone or Tablet: We are all used to getting software updates with our smart devices. The effect on image transmission doesn't seem to be quite as great with phone or tablet software updates as with DJI app and AC/RC updates, but it happens. A common situation is when the GO app requires the smartphone or tablet to be running on a software that isn't outdated. The problem occurs when the device doesn't have enough storage or is too old to get the latest software update. At this time, a device upgrade may be in the near future for that user.

DJI Go 4 App settings

There are certain in-app settings that will help decrease the load on your device, which will, in turn, allow for smoother video.

First up is the video cache. As you may have noticed, your device will save the cached video for you to view at a later time. However, this puts more of a load on your device and can impact the live video quality. Let's turn off “cache during video shooting”, under general settings. Go ahead and clear the video cache while you're here.

Next up are frequencies. Some DJI drone models only operate on 2.4 GHz and others can operate on either 2.4 GHz or 5.8 GHz. Without getting too in-depth, 2.4 is better for longer range but can become crowded as it is a more common frequency. Better for shorter ranges is 5.8 GHz as it is stronger, indicating less latency. Depending on which drone you have, you may be able to toggle between 2.4 GHz and 5.8 GHz.Out of the box, your drone channel mode will be set to auto, but you can change this to custom in the image transmission settings. It's generally advisable to leave it on auto, but if are you having a terrible time with video lag you may want to manually choose a channel. As you can see in the image below, some channels have red, some have green. Pick a channel with a lot of green.

Lastly, some drones allow you to choose the image transmission mode. For smoother video, avoid anything that says “HD”. In custom mode, you may be able to choose an image transmission code rate between 4Mbps and 10Mbps. Pick the 4Mbps. We're just trying to finish the marathon here, not win the whole darn thing.

This isn't a setting, but it's important to note that the image will naturally be more choppy/laggy while you are recording video as your device is having to work harder.

Phone or tablet settings and tips

Let's go ahead and get your device setup for success. Instead of going out and buying a brand new phone, the following settings and tips may just rectify the poor image transmission without requiring you to empty your pockets.

• Turn on airplane mode when getting ready to fly. You will still be able to turn on WiFi manually if you need it to fly when the phone or tablet is in airplane mode. If you have an Apple watch, consider placing it on airplane mode as some have reported this making a significant difference.
• Turn Bluetooth off. 
• Try using a different USB cable. I found one that works perfectly and is just the right size for my iPhone. It can be found on Amazon here.
• Spark owners should use the OTG (on the go) cable instead of flying with WiFi. This will cut down on interference and provide a more stable video.
• I talked extensively about the effect heat can have on your device in Is it Safe to Fly My Drone in Hot Weather, but as a recap: the device will slow down as the temperature heats up. A slow phone makes for poor image quality. In an effort to keep the device cool, close down background apps and take the device out of its case to let it breathe.

Consider your surroundings

Chances are, Peter who lives in the desert is going to have a much better video than Paul who lives in the city. There are a large number of electromagnetic disturbances that operate on 2.4 GHz in an urban area, as well as numerous WiFi signals. If you are noticing terrible video quality while flying, remember that this may be due to your environment. Large metal structures and cell towers are often the culprits.

It's also good practice to always be cognizant of where your RC's antennae are pointed. Configure them in a manner so that they run perpendicular to the AC, and try not to have the drone directly overhead. Signal boosters aren't a bad investment either. Sometimes I feel that they make a big difference and other times I find myself constantly adjusting them because they don't seem to be doing anything. For less than ten bucks, I'd say that they're worth it. Here is a video that discusses antennae positioning in-depth.

I'm sure most of us have gotten the “weak image transmission signal” notification at some point. If you're like me, then this is about the time you start sweating and wondering if you preset the RC signal lost instruction to Return-To-Home. “Yes, of course I set it…well, I think I….shoot”, but you get pulled from your thoughts by the audible notification coming from your RC with a corresponding message that says “RC signal lost”. Too late! Most of us know, but it's important enough to say for those who may be newer to flying. You can give the drone preset instructions on what to do if the RC signal is lost. It gives you three options: return-to-home, landing, and hover. There are very few circumstances where you'd want your drone to land or hover in place when the RC signal is lost so I always have it set to RTH.

To give the drone preset instructions on what to do if the RC signal is lost, go to settings>MC>advanced settings>RC signal lost, from there you can choose between RTH, landing, and hover. 

Try using a different device to see if that's the culprit

An easy way to rule out the possibility that the device you are using is the culprit is by trying a different device. This is one of the first things DJI is going to recommend that you do if you tell them you're having image quality issues. Now, I wouldn't go out and buy a brand new phone or tablet right off the bat; try borrowing one from a friend, uncle, parent, or child first. Make sure the DJI GO app that you download on the borrowed device is on the same update as the one you've been using to fly.

Fly your drone with a different app

Here in San Diego, we have In-N-Out Burger, which is a fast food place that closes at 1:00 AM. If you visit In-N-Out at 12:30 a.m., you are likely going to see at least ten cars in the drive-thru ahead of you. In-N-Out is insanely popular here on the west coast. So what makes this place so darn good? Their menu consists of three items: hamburgers, fries, and milkshakes. Their extreme simplicity is part of what makes them so popular, along with their ability to make a delicious burger. 

So why the In-N-Out analogy? Because I think DJI is trying to do too much with their DJI GO apps. In my opinion, DJI should make an app that is strictly for flying, and another app for everything else (the editor, Skypixel, profiles). I feel that a DJI app that was used strictly for flying would be a lot smoother, take up less space, and get a lot of love from us users.

Enter Litchi, an app that is designed to simply fly the drone. I have both Litchi and the DJI GO 4 app on my phone. If I'm flying with the DJI GO 4 app and I start to get a lot of lag or a choppy screen, I'll switch over to Litchi and immediately have significantly less. The Litchi app is currently 72 MB, whereas the DJI GO 4 app is 440 MB. Sure, there's a lot more that goes into it than just the size of the app, but this gives you an idea of how much DJI is trying to do with their GO apps. This is by no means a full comparison between the two apps, but when speaking specifically to the flying experience, you're likely to have a smoother ride when using Litchi.

Trevor's Take

When I get out to fly, I do so because I thoroughly enjoy the experience. The technology amazes me, I love the breathtaking views that a drone can provide, and I find it simply, fun. So when my screen starts to get those green and black lines, it makes the overall experience just a tad less enjoyable. I'm not currently using any of my drones for professional purposes. While conducting research on this topic, I came upon quite a few individuals that said they lost out on a paid job because of poor image transmission. It's frustrating when a laggy video is present while out there flying for fun, but missing out on a lucrative opportunity because you can't see the screen has to be downright discouraging. What is your experience with a poor quality image? Was there something you did that fixed it? I'd love to hear about any more remedies that weren't mentioned in this post. May all of your la la lag lag laggy (see what I did there?) days be behind you!