Add the HP Sprocket 3x4 Instant Photo Printer to the list of highly portable printers that can serve nicely as a cell phone or tablet companion. Like most of its competition—including the Kodak Step Instant Mobile Photo Printer, our current top pick for wallet size (2-by-3-inch) photos—the Sprocket 3x4 is small and light, includes a built-in battery, connects without wires (using Bluetooth, in this case), and is reasonably inexpensive. (It's $129.99 on Amazon at this writing; list price is $159.99.) Where it differs is that its photos are 3.5 by 4.25 inches. If wallet-size is too small for your tastes, while the printers for 4-by-6-inch photos—like the Canon Selphy CP1500—are too big and heavy, that puts the Sprocket 3x4 in your portable-printer Goldilocks zone.
Portable printers for 2-by-3-inch photos are typically the size of a smartphone, but thicker. The Sprocket 3x4 is only a little bigger than that. Compared with my Samsung Galaxy S20FE, it's about a third wider and twice as thick, at 1.1 by 5.1 by 6.4 inches, and it's barely any heavier, at 12.6 ounces. It can easily fit in a bag, a backpack, or a large pocket, to bring along wherever you like. Track Link Assy
The physical design is a silver-gray flat box complete with a cover (held on by magnets), which you remove to reveal the paper tray. Rounded corners and what look like random darker freckles on the top cover give it a little more stylish look. A status light, in the form of a thin, inch-long bar, stripes across the front, just above the output slot. The left side includes a small power-on switch and a status light, plus a micro-USB port for charging the internal battery.
The first step for setup is to charge the battery, using the USB Type-A-to-micro-USB cable that comes with the printer. No AC charger block is included, but if you don't have one handy, you can connect to a computer's USB Type-A port instead. The specs list the charge time as 2 hours, and a company rep says that it can print 30 photos on a charge.
The physical setup is otherwise standard for a Zink-based printer, which uses heat-activated dye crystals embedded in the paper to create the image. Simply take off the top cover, drop the stack of photo paper in the tray (making sure the blue calibration page is on the bottom), close the top, and turn on the printer. Wait a moment for the calibration page to feed, and you're all set.
The printer comes with a starter pack of five sheets of Zink paper, so you're well advised to buy some supplies along with it. The HP Zink paper comes in boxes of 20, 50, or 150 sheets, with the cost per photo dropping significantly if you get the highest quantity. Based on prices at this writing on the Sprocket printers site, the cost per photo is $1 for either of the two smaller boxes, but drops nearly by half—to 50.4 cents per piece—for the 150-sheet box.
For all three quantities, the paper comes in foil packs of 10 sheets each, which is the maximum paper capacity for the printer, and each pack of 10 includes its own calibration page. The paper has adhesive on the back, with a peelable backing, so you can stick the photos wherever you like.
In addition to setting up the printer, you'll need to download and install the HP Sprocket app, available for Android or iOS mobile devices only. (There's no option for printing from a PC.) I found it easy to set up, connect to the printer from my Android phone, and use for basic tasks, including picking a photo from my phone's Gallery and printing it.
The app offers much more than just basics, including the ability to take a picture from within the app; create collages of two or four pictures in an assortment of layouts; adjust brightness and contrast before printing; and add text, frames, or stamps. It also lets you view and print photos from your Instagram, Facebook, and Google accounts. The help feature isn't all that helpful, though. The section on editing photos, for example, doesn't tell you how to call up the editing commands. You can find more useful instructions and FAQs for using the app on the Sprocket website.
As with all Zink printers, the Sprocket 3x4 offers decent output quality, but it is a noticeable step down from dye-sub and instant-film printers. In my tests, the printer handled skin tones ably, along with greens and blues, which means it scored reasonably well on closeups of faces and on outdoor pictures with lots of greenery. However, it tended to dull down reds and reddish browns, darken images noticeably, and drop shadow detail. The photos are also limited to white borders all around, with the Sprocket 3x4 lacking an option for borderless printing.
The claimed speed per print is "up to" (meaning "as fast as") 68 seconds, which closely matches the fastest that I timed, at 70 seconds from print command to finished photo. The slowest photo print I timed was 81 seconds. The only competitor we've tested with the same photo paper size (but a smaller image and bigger borders) is the Fujifilm Instax Link Wide, which took about 30 seconds from print command to spitting out the instant-film photo. (But note that it then took a few minutes for the film to develop in full.)
Times for other printers with different photo sizes aren't directly comparable. As points of reference, however, note that the Zink-based Kodak Step Instant Mobile Photo Printer averaged just under 60 seconds for 2-by-3-inch prints, the dye-sub-based Kodak Mini 3 Retro (3x3) Portable Printer averaged 43 seconds for its 3-by-3-inch dye-sub prints, and the Canon Selphy CP1500 served up a blazingly fast 38-second average for its 4-by-6-inch dye-sub prints. That puts the Sprocket 3x4's speed in the same bucket as its quality: more than acceptable, but not a standout.
The key question for choosing any snapshot printer like this one is whether it can print the photo sizes you want. That makes the HP Sprocket 3x4 a good candidate if you want photos up to 3 by 4 inches and no larger. If you want 2-by-3-inch wallet-size photos from it now and then, you can always cut larger photos down. But if the 2-by-3-inch size is all you need, consider the Kodak Step Instant Mobile Photo Printer, our current top pick for that size, and eliminate the extra step of trimming the photos. Similarly, if you need to print larger images, up to 4-by-6 inch standard snapshots, consider the Canon Selphy CP1500, our top pick for the bigger size.
If the Sprocket 3x4 output is the right size for your needs, and you appreciate the sticky-back stock, it could easily be your best choice. But you might want to compare it to the Fujifilm Instax Link Wide, which offers better output quality, albeit at a significantly higher cost per photo. Also consider the Kodak Mini 3 Retro (3x3) Portable Printer, which, like the Instax, offers better output quality. Its 3-by-3-inch square format will force you to crop pictures differently, but it's ideal for square-format Instagram photos.
Most of my current work for PCMag is about printers and projectors, but I've covered a wide variety of other subjects—in more than 4,000 pieces, over more than 40 years—including both computer-related areas and others ranging from ape language experiments, to politics, to cosmology, to space colonies. I've written for PCMag.com from its start, and for PC Magazine before that, as a Contributor, then a Contributing Editor, then as the Lead Analyst for Printers, Scanners, and Projectors, and now, after a short hiatus, back to Contributing Editor.
I'm pretty sure I'm the only person who worked on every Project Printer blockbuster PCMag ever produced, often writing 15 or …
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