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The best scanner apps for mobile devices help you capture images with minimal distortion, save them in useful forms and share the files online easily — without the need for a cumbersome desktop scanner. Scanner apps can help you archive personal documents or family vacation photos, turn tax forms into portable document format (PDF) documents, capture travel receipts for expense reports or turn school handouts into readable text.

To help you choose the best scanner app, we tested five scanner apps on our iPhone, scanning several boxes of photos and documents. We tested CamScanner Premium, Genius Scan Ultra by The Grizzly Labs, Microsoft Lens, PhotoScan by Google Photos, and SwiftScan Pro by Maple Media. We also consulted with two experts who gave us archiving and organization tips on how to prepare for our large scanning project.

After several weeks of testing, we concluded that choosing the best app is a matter of matching your particular scanning needs with an app’s strengths. If you told us we could only continue using one app, then we’d name Genius Scan Ultra as our overall pick.

Genius Scan Ultra

Best scanner app for mobile overall

During our testing, we found Genius Scan Ultra to be the fastest scanner app, and also the best at performing text recognition on documents. While saving scanned items, we liked the app's ability to accurately suggest tags based on location, calendar events and document contents.

During testing, Genius Scan Ultra was splendid at capturing our pile of documents, with a fast, touchless scan; accurate text recognition; and support for our favored online storage. Its speed at scanning multipage documents puts it just a skosh ahead of CamScanner Premium.

What we liked about it

When we pointed our phone at a document, Genius Scan Ultra easily detected the page’s shape and displayed it onscreen with a bright orange-highlighted box (see photo example below), even if our fingers were a little off-kilter and the page or item was askew. Then the app captured the image and corrected the perspective — without our touch.

Esther Schindler/CNN Underscored
Genius Scan Ultra brightly highlights the item in orange that it’s about to capture, which gives you confidence that it’s grabbing the right information. Then the app straightens, aligns and crops the image — without you touching a button.

File name templates were easily edited. We could add tags (recipe, Frankfurt) to make searching easier. Genius Scan Ultra offers tag suggestions based on location, calendar events and document contents. For instance, it picked up “contract” from an optical character recognition (OCR) scan, and scanning an event program caused the app to (accurately) suggest a file name of Jan. 11, 1973.

We were able to use Genius Scan Ultra to save single-page scans as plain text or Microsoft Word (using OCR) and multi-page scans as PDF documents (you can also do the latter, optionally, with encryption). The app also let us save single-page scans as JPGs (multi-page scans are exported as PDFs by default). After making sure text recognition was applied, we were able to save our 1973 event program cover as a JPG and share it to Facebook.

While the paid version includes unlimited cloud storage, you’ll probably want to share the files elsewhere. The options for exporting scanned files are extensive, with a subset including Box, Dropbox, Evernote, Google Drive and Microsoft OneNote. Or you can access files on your local network using Wi-Fi sharing.

Do you need to digitize a lot of documents quickly and save them to a cloud platform? Then this is the easy pick, and again our favorite. That orange highlight won us over.

What we didn’t like about it

If your archiving goal is text recognition, then Genius Scan Ultra is the winning app; it performed the best among the five apps tested. The only real items on our wishlist for Genius Scan Ultra would be that we didn’t need to budget extra time for nitpicky editing. We had to clean up the text a bit after scanning (see photo example below), but still, it does the best text recognition of the bunch.

And while Genius Scan’s Basic version is a fully functional free app loaded with features, in order to use the text recognition (OCR) and PDF encryption features, you need to subscribe to the Genius Scan Plus ($1 per month, billed monthly at The Grizzly Labs) or Genius Scan Ultra version.

Esther Schindler/CNN Underscored
Genius Scan Ultra’s text recognition is the best of the bunch, but still far from perfect. Do budget time to clean up the text a bit.

Bottom line

This was the coolest of the scanner apps for mobile we tested and the most fun to use. It worked so fast that we felt like a movie spy taking photos of top-secret documents in an underground lair. Click, click, click…and a 12-page document was captured and instantly saved online.

How to choose a scanner app for mobile

Smartphone camera quality is remarkable nowadays, but it’s optimized for photography, not scanning. When you capture a document — a restaurant menu, a high school graduation program, an accounting form — it’s important to square up the image, reduce glare and (optionally) automate text recognition.

Picking the right scanner app for mobile depends significantly on what you plan to scan and what you do with the results. The cost is minimal — in fact, two of the ones we tested are free — but the suitability-to-task varies considerably.

Broadly, there are three categories of items you might scan: images (photos or anything stored as such), documents (usually saved as PDFs) and text (results saved in Microsoft Word or as another editable document where the app employs OCR to recognize the text).

Some scanner apps for mobile focus on one element at the expense of the others, so choose an app that matches your scanning needs. Google’s PhotoScan and Microsoft Lens excel at photo capture but aren’t especially helpful for other purposes. That’s fine, if your project goal is to digitize Mom’s photo albums.

However, if you plan to scan old books, such as Great Aunt Eva’s autobiography, you need an app that can handle your efforts to hold the pages apart. A book or magazine that tries to flop closed while you’re scanning introduces image distortion that’s hard for text recognition (see photo example below).

Esther Schindler/CNN Underscored

How important is document quality to you? Is “close enough” enough? A readable photo of a kid’s drawing is adequate for family kvelling. On the other hand, capturing important legal documents (such as employment contracts) or family heirlooms (Grandpa’s passport) may justify extra time fiddling with the image to get things just so. Some scanner apps for mobile have more features to support this effort as well as tools to annotate, sign and fax documents.

Another decision criteria: What are you going to do with the results? You can always save files to your smartphone. But it saves time if you match the app’s supported online platforms to software you already use, such as Dropbox or Microsoft Office.

Esther Schindler/CNN Underscored

How to prepare for your archiving project

Unless your collection fits into a shoebox, your scanning project will likely be more work than you envision. Plan ahead. Organize your materials before you get started. If you have a lot of photos and documents, organize them into different containers according to type first (see photo example above).

“Doing so allows you to scan items in an easy-to-manage fashion,” points out Brooke Lake, founder and lead archivist at Monocurate in Austin, Texas. Monocurate is an archival company specializing in the organization, preservation and digitization of multimedia collections.

According to Lake, organizing beforehand lets you prioritize the material. “Invest time in digitizing the most fragile first,” she says, “such as paper that’s falling apart, newspaper if you can’t find it online, and photos that are fading or damaged.”

“I recommend scanning 10 items and making note of how long it took,” advises Melissa Gugni, a professional organizer and owner of Melissa Gugni Organizing in the San Francisco Bay Area. Her firm helps clients organize, declutter, create systems and style their home, office or business. “Do some quick math to estimate how long your project will take.”

Don’t feel that you need to include everything just because it’s in the box. “Be discerning,” says Gugni. “Remove duplicates, blurry photos, photos that have people in them that you can’t recognize and, most importantly, boring photos.”

Another less-obvious archive question involves making the results discoverable. If you capture your family’s photo history, at some point you will want to find every photo of your brother or “cat pictures taken between 1920 and 1960.” In large part, that becomes another task after you finish digitizing the collection, but the tagging in the three paid apps we tested — CamScanner Premium, SwiftScan and our overall pick Genius Scan Ultra — smooths that process.

Lake recommends standardizing file names at the start of your project so you can find the digital copy easily. Use file names like “1983_SmithDiary_pg3” rather than “7823e83dw434Xs5.”

“Standardizing the file name allows you and your loved ones to identify the proper files and allows you to search your digital files with ease,” she says.

How we tested

During our pre-testing research, we found a large number of scanner apps to choose from. We selected our five candidates to test based on desired features, user reviews and availability on Android and iOS mobile platforms. We downloaded each of the five scanner apps to an iPhone. We tested each of the apps with the following criteria in mind: scanning ability, ease of installation and configuration, functionality, sharing options and OCR capabilities. We also considered the apps’ affordability and payment options.

Scanning ability

We gave these five scanner apps a workout, scanning dozens of documents from our impressively large collection of items that we refuse to label “hoarding.” A side-by-side comparison of each app was performed using a document test suite that encompassed a photo of us on our 4th birthday (surrounded by gifts for, surely, our first product review), a typed short story written by our father circa 1940, a restaurant receipt, a Museum of Holography newsletter from 1982 (what was that about being a packrat?) and a fill-in-the-blanks registration form for a printer that broke 10 years ago (okay, perhaps “hoarding” is the right term).

Ease of installation and configuration

We found that the scanner apps have several attributes in common, beginning with ease of installation and configuration. You could recommend them to your most tech-averse relatives without fear of family tech-support calls.

Functionality

The basic functionality is straightforward. We took a picture of each photo or document, and then cropped the images. We also changed the contrast if needed, but in general, the apps automated this process with impressive accuracy.

Sharing options

All the apps we tested let us use the typical “share” dialog built into iOS, so with all of them, the basics were covered. We could email the results, send via text, print or post to a social media website such as Facebook.

OCR capabilities

In general, OCR capabilities exist in these apps but are imperfect. Even the 1940 short story — hand-typed in a monospace typeface — was converted with odd spacing and characters. So expect to use these tools as a starting point, but be ready to edit.

Two apps, PhotoScan and Microsoft Lens, were less about documents and more about integrating a photo-capture process into their other applications. Instead of taking a portrait of a live person, for example, you’re taking a picture of a photograph; the app’s role is to enhance the images.

Payment options

While not a criteria for winning the test round, we did note the apps’ affordability and payment options. While you can pay for an entire year, the paid scanner apps can also bill you monthly. Thus, you need only a short-term financial commitment should you finish your scanning project within a reasonable amount of time. All three paid apps offer a trial period so you can experiment, or you can stick with their free, though limited, versions.

Other scanner apps for mobile we tested

CamScanner Premium

$5 per month, billed monthly at CamScanner

A well-designed user interface is a thing of glory, and CamScanner Premium is a fine example of software that packs a lot of power into a deceptively simple screen. The features one uses most often are front and center. The usual tasks, such as scanning a paper document to PDF (one page at a time or in batch mode), took us just a moment or two. But then we kept discovering the app’s more sophisticated features, always with a little gasp of, “Oh, how cool!”

For instance, we learned we could capture text directly to Microsoft Excel, snapping a photo of our computer screen or of a printout. The scan-to-text option performed OCR and translated the results instantly into our preferred language. The app can translate into 40 languages (including Greek, Hebrew and Japanese). Its book scan captured two pages of our document at a time and provided us with the text and images separately.

The app has a lot of annotation options; we could smudge and highlight, and add watermarks and signatures. We used our phone to capture a Microsoft PowerPoint display during a meeting instead of taking notes. CamScanner Premium let us organize our results in folders and modify the file name template to meet our own standard (year-month-day or December or Tuesday).

CamScanner Premium’s built-in tags (business card, recipe, whiteboard) helped us easily categorize documents. Finally, the Android and iOS apps include 20 GB of cloud storage.

SwiftScan Pro

$7 per month, billed monthly at Maple Media

On paper (so to speak), SwiftScan Pro shares many of Genius Scan Ultra’s features. Both apps have a no-touch setting that let us capture documents automatically and both let us save files as PDFs, whereupon we could add notes, signatures, redactions and highlights. SwiftScan Pro also let us save files as JPG images and it performed some OCR (plain text only, however, with no formatting).

Uniquely among the apps we tested, SwiftScan Pro was able to scan QR codes and barcodes and took action on the results immediately. For instance, based on the document’s contents, it searched the internet for a barcode match and gave us an option to call a phone number or open a URL. It also has a scanning option for whiteboards and business cards and could import images from our photo library.

Editing file name templates is one area in which SwiftScan excels. In addition to letting us include date and time in our file names, it let us append our current location (city, state, country) and use custom file name separators. As with the other apps we tested, you can save SwiftScan Pro’s results in a wide variety of platforms, including Dropbox, Evernote, Google Drive, iCloud and Shoeboxed. You can instruct SwiftScan Pro to save files to your preferred location automatically.

All that sounds like it’s on par with its competitors. But in practice, SwiftScan Pro had trouble on the same documents that Genius Scan Ultra accepted without a qualm, under the same lighting conditions. SwiftScan Pro instructed us to move closer, change our camera angle and ultimately, to just take the photo manually. The app works, it just isn’t as accurate, as fast or as enjoyable to use.

Microsoft Lens

Free at Microsoft

For a free app, Microsoft Lens let us accomplish a lot. We were able to capture photos, create PDF documents and turn images into text. We saved files in other formats, too, primarily to Microsoft software such as Excel, OneDrive, OneNote, Word and PowerPoint. (If you use Microsoft Office extensively and want to add to its scanning functionality, then you’re bound to appreciate this app.)

Microsoft Lens has dedicated settings for iPhoto imports, plus we were able to capture business cards (saving contact information in OneNote) and whiteboards (the results were essentially a photograph). We annotated images with text or ink (that is, scribbled in color on the image) and applied image filters such as sepia and auto-enhance.

That would be impressive enough for a free app, but Microsoft Lens let us do some things that the other apps didn’t. We digitized printed and handwritten text with surprisingly good results. Plus, an immersive reader let us scan a document and then the app read it aloud — a handy feature if you find yourself in a dark restaurant with hard-to-discern menu fonts.

Microsoft Lens does some auto-cropping and image manipulation, but those features weren’t as extensive as they were in the paid apps we tested. Its OCR results are adequate for casual use but not outstanding. The app also doesn’t include file name templates, so we had to establish our own naming conventions.

PhotoScan

Free at Google Photos

Glare and image distortion are the primary differences between taking a “real” picture and scanning a printed photo. Reflective coatings make photos shiny, which throws off smartphone cameras. And it’s hard for us humans to hold still enough to line everything up, so your efforts to “just take a picture of the photograph” generate skewed images that are hard to fix.

Enter Google’s free app, PhotoScan, to digitize your “to archive” pile and automatically upload the images to Google Photos. Think of PhotoScan as an add-on to Google Photos rather than a general scanning app — it does essentially nothing with text-heavy documents or ones you’d prefer to save as PDF. It just doesn’t capture non-photo documents well. That said, it does a fine job of capturing photos.

We took a picture of our photograph using PhotoScan. The app guided us through a short process of pointing the camera at four white dots overlaid on the image, which helped PhotoScan line things up, correct distortion and resolve glare. That was mildly fun to do. The app then automatically cropped the photo and rotated it to ensure that the image was right side up. (Naturally, we could have also cropped the photo manually, but we felt we didn’t need to.)

PhotoScan also did an impressive job of capturing a photo embedded in a larger document — but it captured only that photo. The front page of our Museum of Holography newsletter included a black-and-white photograph; PhotoScan ignored everything except the photo. Repeatedly. It was both impressive and annoying.

There isn’t much else that you do within PhotoScan. If you want to add tags, adjust color and contrast and so on, you tackle those tasks in Google Photos.