You can't read an ad for a new digital camera without being overwhelmed by a slew of mighty-sounding features. But what the manufacturers don't want you to know is that a lot of those highlighted features...they don't really matter, at least when it comes down to image quality anyway. Don't be swayed by marketing tactics—learn what camera features are actually trivial, and which ones are quite substantial.
Megapixels really don't matter—at least not in the substantial way most people think. In fact, there's such a thing as too many megapixels. Sensor size is a much better indicator of image quality. If a manufacturer tries to cram too many megapixels onto a small sensor, it can actually harm the image quality rather than help it.
If you only consider one factor when comparing digital cameras, make it sensor size, (the bigger the better). Large sensors mean better resolution as well as better low light performance. Ignore the megapixel number and focus on the sensor size. Since these sizes are listed as fractions, they can be a bit harder to compare—if you're having trouble, head here to make sense of camera sensors.
I have yet to meet a touchscreen on a camera that I actually like—and that doesn't make me feel like I have fat fingers. Navigation is much easier using manual controls and physical buttons then navigating with a touchscreen that's not quite accurate. Touchscreens do often offer touch-to-focus, but there's often another method of manual focus that works just as well.
Optical Zoom: Substantial
Simply put, a good zoom will help you get shots that a camera without simply can't achieve. Just make sure the zoom number is optical—digital zoom only crops the image, and you can do that with any camera and some imaging software.
Frames per second is how fast a camera can take burst shots—but it's a good indicator of overall speed as well. A fast camera can mean the difference between missing the right moment and nailing the perfect shot. Speed is important for sports photography—but also other types as well. If you take pictures of little kids, for example, speed is a necessary feature.
HD video: Substantial (But Beware...)
Having HD video is a big plus, unless of course you own a separate HD camcorder. Don't just look at 1080p HD vs 780 HD, though. When considering the video quality on a camera, you should also compare fps (higher numbers are better as lower will result in choppy-looking motion) and bit rate (written as MBPS, a higher number means better quality).
Wi-fi is becoming increasingly popular on digital cameras—but some consumers use it all the time while others don't use it at all. Determine which type of user you are before giving a lot of merit to whether or not a camera includes wi-fi. Wi-fi allows you to upload an image from the camera to your smartphone—from there you can use image editing apps or upload it to the web. Most wi-fi equipped cameras also allow you to use your phone as a remote to snap pictures without actually standing at the camera. If you're a big Instagram user, wi-fi will be a big plus for you, but if you hardly upload images to the web at all, it might save you a few bucks to go with a camera that doesn't have wi-fi.
GPS will mark where an image was taken. It's useful for organizing photos based on location, especially if you travel, but beyond that doesn't have a whole lot to offer. Actually, GPS can be a bad thing—if you upload a geotagged image to the internet, anyone with a bit of know how can figure out exactly where the photo was taken. Not exactly something you want if you upload pictures of your kids or your home to Facebook.
Image Stabilization: Substantial
Image stabilization can help prevent blurry photos—it's especially useful on cameras with long zoom ranges or when taking images in low light. If you are shopping for a mirrorless or DSLR, the image stabilization might be in the body of the camera—or it could be in the lens. In-body image stabilization will save you money in the long run since the lenses are cheaper, but either form offers similar benefits to image quality.
Rugged cameras are excellent options even if you don't plan on doing any snorkeling. Say a drink spills in your bag or you get caught in a downpour or your toddler tosses it in the toilet—you don't have to worry about a ruined camera (though you should do some disinfecting in the last scenario). But waterproof cameras are also often sealed from sand and dust. Simply taking a regular camera to the beach can get sand particles caught in the lens barrel, causing the camera to display a “Lens Error” message and stop taking pictures. Waterproof cameras can be quite a bit more expensive though, but don't write them off completely because you don't have any actual plans of going underwater.
I would never buy a serious camera without RAW—but I also own Photoshop and like to edit my shots. If you're an enthusiast or even a beginner looking to get serious, you should get a camera with RAW capability. If you're just looking to take pictures of your kids as they grow and don't own or even plan to own image editing software, then RAW is probably a feature you won't use anyways.
Bright Lens: Substantial
Sensor size and lens quality are the two biggest indicators of image quality. A bright lens will have a low f-number, like f1.8—these lenses are capable of letting in more light and work well in challenging low light shots. Just remember, big sensor number, small lens number when comparing cameras.
Cameras that are smaller are better for travel, and you'll likely get them out more often. While size is important, just how much of a size difference is worth an extra $100 or so to you? An advanced compact is easier to travel with than a mirrorless, and a mirrorless easier than a DSLR. But when comparing a mirrorless to another mirrorless, for example, the couple ounces that make a camera “the smallest yet” isn't going to make a whole lot of a difference—as soon as you add a lens, it's not pocketable anyways (and pleas don't store unprotected cameras in your pockets). Small cameras are good—just make sure you're not paying a premium for it.
Tilting LCD screen: Trivial
LCD screens that tilt are a fun feature—but they shouldn't be a deciding factor. On a DSLR, the live view that's required to use the tilting viewfinder is often a bit slower than the optical viewfinder, which can mean missing a shot just to use the viewfinder. Selfie-designed compact cameras with tilting screens are becoming popular—but if the camera has wi-fi, you can use your phone to see what you're shooting and remotely trigger a self portrait. They're fun—but don't put too much importance on them.
Every try to read the screen on your smartphone in bright sunlight? That's why viewfinders still come in handy, even if you prefer to use the LCD screen to compose your shots. It's often easier and more comfortable to use an optical viewfinder, so don't skim over this feature.
Cameras come with a wealth of features—some of them make a huge difference, while others you may hardly use at all. Which features are more important to you will depend a little bit on your shooting style; things like how often you travel and what you typically take pictures of should come into play when determining which features are more important. Some features are more marketing than functional, while others make a big impact on functionality and image quality.
We want to hear from you—what features are most important to you when shopping for a new digital camera?