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Replay XD Prime X review: Solid 1080p video, pro-centric features, ultracompact waterproof body -- all at a reasonable price

For its fourth-generation HD action cam, Replay XD delivers a small waterproof camera with higher-end features, but at a reasonable price.

Joshua Goldman Managing Editor / Advice
Managing Editor Josh Goldman is a laptop expert and has been writing about and reviewing them since built-in Wi-Fi was an optional feature. He also covers almost anything connected to a PC, including keyboards, mice, USB-C docks and PC gaming accessories. In addition, he writes about cameras, including action cams and drones. And while he doesn't consider himself a gamer, he spends entirely too much time playing them.
Expertise Laptops, desktops and computer and PC gaming accessories including keyboards, mice and controllers, cameras, action cameras and drones Credentials
  • More than two decades experience writing about PCs and accessories, and 15 years writing about cameras of all kinds.
Joshua Goldman
7 min read

There are a lot of action cams available, but few offer a feature set targeted at professional use and results the way Replay XD has done with its Prime X camera. And it all starts with its lens.


Replay XD Prime X

The Good

The Replay XD Prime X is one of the smallest, lightest, full HD waterproof action cams available. Its design and features make it easy to use, from mounting it just right to changing settings on the go. An external mic adapter is available, and its HDMI out supports live uncompressed video to a display, recorder or transmitter. It's also well priced given all that it can do and its included accessories.

The Bad

The camera's battery is built-in, so no quickly swapping batteries for more power. The internal mic's performance is a little inconsistent. Several settings can only be adjusted by editing a text document stored on your microSD card. A tripod mount isn't integrated into the body.

The Bottom Line

The Replay XD Prime X might not have the name recognition of others in the category, but thanks to its lightweight, ultracompact and waterproof body; solid 1080p video quality and pro-centric features, it deserves a spot on your short list.

The f2.7 lens (T2.8 for the filmmakers out there) Hyperion CinePrime X has a 140-degree angle of view. It was exclusively designed for this camera using aspherical, antireflection-coated, all-glass elements including special low-dispersion elements used to reduce chromatic aberration. A replaceable impact-resistant glass lens cover protects the whole thing.

Behind the lens is a 1/2.3-inch 16-megapixel CMOS sensor, which the company says uses 33 percent less power and has higher sensitivity and better dynamic range than previous models. With it, the camera can record video at up to 1080p at 60fps and 720p at 120fps but also has cinema settings for 24 and 48fps.

Sarah Tew/CNET

Now, that's a lot of specs and details that may not mean much to you, especially if all you're interested in is if it's better than a GoPro. The answer to that really comes down to your needs, so it's not a simple yes or no answer. But what I can say is the Prime X is a standout for its features and design at its $300 price. Pricing in Australia is AU$395, and in the UK through Amazon and other dealers it's about £200, so you'll have to weigh your options at those prices.

Design and features

The tubular aluminum body measures 1.2 by 3.9 inches or 30 by 98mm and weighs only 3.5 ounces or 99.2g. By comparison, it's roughly the size of a roll of US quarters, but less than half the weight. That allows you to put this camera -- or two or three of them -- where others won't fit.

Minor impacts from falls or debris shouldn't pose a problem, and its removable lens cover means you don't have to worry about accidental scratches. Also, as long as the rear cap covering its Micro-HDMI, Mini-USB ports and microSDXC slot is screwed down tight, the camera is waterproof without an additional housing down to 10 feet (3m). A dive housing is available should you want to explore down to 197 feet (60m).

Sarah Tew/CNET

Short of using zip ties or duct tape, there's no way to mount the camera on its own, which is the biggest issue I have with the design. That, and the aluminum body acts as a heat sink, so it can get hot with extended use (though it didn't seem to have an impact on camera performance).

Instead, what Replay XD uses are plastic collars that wrap around the middle of the camera with two tabs on the bottom, which mount securely into the company's SnapTrays. Arrows on the collar's top can be lined up with etched markings on the camera so that, if the camera is mounted upside down, for example, you can rotate the Prime X into the correct position. Once locked into a SnapTray, the camera will not rotate, so you don't have to worry about your shot suddenly being crooked or upside down.

The Prime X comes with a nice assortment of accessories (one of the nicest I've seen in a while) that includes two adhesive SnapTrays -- one curved, one flat -- and an extra 3M adhesive pad. There's also a SnapTray with a tripod mount. To slide into the SnapTrays, you get a LowBoy mount for when you want the lowest profile possible and a locking tilt mount so you can angle the camera up or down.

Sarah Tew/CNET

Also in the box is a 4GB microSDHC card (cards up to 128GB are supported); a microfiber camera pouch; a Mini-USB cable; a set of stickers to place over the internal mic to reduce wind noise; a printed user guide; and a nylon case to store everything in.

Lastly, the internal 1,700mAh battery is capable of continuous recording for up to 3.5 hours on a single charge. A representative for Replay XD said this was achieved recording at 720p at 60fps, and that they had hit 2.5 to 3 hours on 1080p at 60fps.

In my tests, I averaged 1 hour and 45 minutes at 1080p60, but that was at its highest bit rate of 25Mbps, which is the best quality video you'll get from the Prime X. All in all, that's not a bad battery life, especially given how small the camera is. However, since the battery is built-in, you'll either need to recharge once the battery is drained or connect an external battery or power cable to keep recording.

Sarah Tew/CNET

Shooting options

There are no 4K-resolution options here, so if that's a requirement for you, you'll have to move on (and pay more money). The Prime X maxes out at 1080p at up to 60 frames per second, 720p at 120fps or 480p at 240fps. If 4:3 format is more your thing, it'll do 1,280x960-pixel resolution aka tall HD at up to 60fps.

For photos you can shoot one at a time, in bursts of 3 or 8, and continuously for creating time-lapse videos at 3, 5, 15 and 30 seconds at 12- (16:9), 14- (3:2) or 16-megapixel (4:3) resolutions. Field of view can be adjusted as well, going from an ultrawide angle of 140 degrees down to a narrow 70 degrees with a stop at 116 degrees in between.

Most of these settings can be selected using the buttons on the back of the camera. A series of color LEDs lets you know which mode, resolution and frame rate you're using, though thankfully you won't need to remember what all the lights mean because Replay printed a key inside the rear cap.

All of the camera's settings can be adjusted by changing values in a text document that gets stored on your microSD card when you insert it into the camera. This includes settings for bit rate, exposure compensation, metering, white balance, contrast, sharpness, saturation and audio gain.

Some, but unfortunately not all of these can be tweaked with the Replay XD app for Android and iOS, so every once in a while you'll need to sit down at a computer to adjust the Prime X.

Screenshot by Joshua Goldman/CNET

The camera has built-in Wi-Fi that you can connect to with a mobile device. Once connected, you can use the app to see a live preview as well as a live stream while recording; control the camera for starting and stopping movies and taking photos; review and download content on the camera on your smartphone or tablet.

When the Prime X first launched last October, the wireless performance was shaky, but a couple firmware updates later, the stability has been considerably improved. However, if you want or need the capability to live-stream from the camera, the Micro-HDMI jack gives you uncompressed output at 1080p60 or 1080i60.

Video quality


Replay XD Prime X

Score Breakdown

Design 8Features 8Performance 7Image quality 7