The Spark weighs about 0.7 lbs (300g), and the body is about the size of a soda can (if a little taller and slimmer). The arms don't fold down like the Mavic, so Spark's total footprint is actually a bit wider (though shorter) than its older sibling when you're carrying it. The included case makes portability a cinch, though -- it fits in most backpacks with tons of room to spare.
That said, Spark packs a surprising amount into that tiny form. There are forward-facing obstacle avoidance sensors (you'll still need to be careful flying sideways or backward, as with the Mavic) and there are downward camera sensors that track the surface below. This means Spark can hold its position indoors without GPS (something it does incredibly well, I learned, much to the chagrin of my cat).
Spark has a 12-megapixel shooter good for video at 1080p (30fps) that delivers great, fish-eye free photos and video. Mavic has the same size sensor, but it can capture clips all the way to 4K (plus it has a bunch of specialized shooting modes). Spark theoretically could shoot at 4K too, but uses electronic image stabilization that eats up some of the extra pixels available. As for battery life, Spark can fly for about 16 minutes per charge (my experience was a shade under this), while Mavic holds itself in the air for twice that. But why compare two drones that are clearly meant for different people? Because I'm not entirely sure that they are.
What's really new here is "gesture control." Hold DJI's diminutive drone out on your hand, tap the power button twice, and it'll launch itself. You can guide it in the air by moving your extended palm and shoot perfect impromptu selfies. The problem I discovered is that you can't take selfies in gesture mode alone.
I learned this only after throwing my hands up in the "picture frame" gesture at the Spark way too many times to no effect. Each time, Spark's lights would flicker to indicate it thought I wanted to move it with my hand, not take a photo. And then, well, nothing. I kept trying, but several more attempts all failed. After consulting the instruction manual, it seems to indicate (which DJI eventually confirmed) Spark needs to be in ActiveTrak mode for the photo gesture to work. ActiveTrak is when the drone follows your body via camera-tracking. Once I tried this, the "frame" gesture worked every single time.
You might ask, "What's the problem here?" I guess I was expecting I could position the drone with my hand, throw the gesture and get a picture. But once you've got it where you want it, putting it in tracking mode causes Spark to fly up and backward a few meters (and then you initiate the photo). Perhaps I am being a bit unfair about this one minor point, but the gesture to enter ActiveTrak isn't recognized consistently, requiring a few attempts to trigger, sucking some of the spontaneity out of the moment (and changing your framing since it's moved). DJI tells me you will eventually be able to do it all as I imagined, but for now, at least, no dice. You can always trigger photos from the app, of course, but throw-and-photo is the dream these mini-drones promise, but we're still a hair away.
As a rule, I am not a fan of flying drones with just a phone, but the DJI Go app is what makes Spark a lot more useful. Go shows you a live feed from Spark's camera, and it also imitates a conventional controller with virtual on-screen "sticks". With these, you can fly Spark much farther away than with gestures, with more control, and it actually works better than most other app-controlled drones (like Dobby). You can, of course, initiate a photo or video from the app, change camera modes, access all the drone settings and see vital info like battery life, GPS info and more.
While DJI made the experience of flying with an app the best I have tried, I'm a stickler for real controls. If you want to get a drone up in the air and place it somewhere with confidence, you can't beat physical sticks. If you want to buy Spark with a controller, it'll cost you $699 (rather than the drone-only $499). That closes the gap with Mavic enough for it to be a real dilemma ($999 with controller, $759 without). Yes, $300 is a decent jump, but considering the extra battery life, better video, and all-round-awesome flying experience the Mavic delivers, it's an excruciating decision -- at least, for me.
The intelligent flight/camera modes available in the app are also pretty impressive. I've already mentioned gesture control and ActiveTrak. There's also QuickShot, which gives you four preprogrammed drone maneuvers (like orbit and "rocket") that let you grab cinematic video clips. Modes like TapFly, on the other hand, take the brains out of flying; you tap somewhere on the video image on screen, and Spark will fly toward it.
These are all great, yet varying degrees of terrifying -- as the intrepid little drone starts moving on its own, a sense of powerlessness overcomes you (at least initially). The first time I used "Dronie" mode (yep, drone-selfie: Spark faces you, but flies up and backward rapidly), I wasn't sure it was going to stop. It did, of course, lingering near a warehouse as a speck in the distance. I called it home via the app without incident, and was, of course, flying somewhere without tall buildings or obstacles, but how long before someone prods that button without really thinking it through?
While the app and smart features are a mixed bag, Spark itself is a solid, agile aircraft. I took it flying on San Francisco's Treasure Island on an incredibly windy day, and I'll admit I didn't have a lot of confidence it wouldn't get blown into a tree or building. But those doubts evaporated after about three seconds. The plucky little thing held its position, shrugging off multidirectional gusts of wind like a champ. The gimbal (camera stabilizer) has only two axes (the one that's missing is "yaw"), but the video doesn't seem to suffer because of how steady it is in flight.
The battery life, while only about a quarter of an hour, is actually quite a long time in drone terms -- at least at this size. The problem is that my first few flights were pretty much a wash as I spent that time coming to grips with the controls, checking all the menu options and so on.
It's worth pointing out that Spark can be charged by micro USB, so if you have a battery pack with you, you can top it up while you get some lunch. It'll take a while longer charging this way than plugging it into a wall, but I really appreciated having the option.
Despite an all-around positive experience, I'm unsure how to feel about the Spark. Technologically, it's impressive. Aesthetically, it's attractive. Yet it's just not quite the spontaneous, simple experience it needs to be for new pilots. Nor is it quite the video drone that creative users might require.
If I was looking for a drone that was easy to carry and grab great aerial video, I'd probably go with Mavic. Not just because I prefer something built for manual control first, but also for the more comprehensive choice of video features. But those things might not be as important to you. If you just want something casual, then the $499 price might just be a little out of the impulse-purchase range.
My suspicion is that Spark will get better with age. And I don't mean, "wait for version two." DJI has made huge strides with its software in recent years. When it launched its camera-based tracking on the Phantom series, it was a bit hit-and-miss. Just turning to your side could throw it off. Now, it's pretty rock-solid and can even tell the difference between people, bikes (well, people on bikes) and animals. The gesture-control features here feel like the same thing.
The good news is that since the Mavic was released it has been given several updates that have improved camera stability and added new photo and video modes. My gut tells me that Spark is about two or three updates away from being the product that we wanted at launch. In the meantime, Spark is a bunch of fun, with a whole lot of potential. Potential which I hope DJI fulfills.