Comparison

LSI Calculator vs Doc Scan:OCR and PDF Scanner

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

LSI Calculator

This app provides tools and educational resources to help users manage water systems, focusing on eco-friendly treatments for pools and spas. It aims to make water maintenance accessible to everyone, regardless of their experience level.

Highlights
  • Water science education
  • Pool and spa water management
  • Eco-friendly treatment guidance
  • NSF/ANSI Certified product information
  • Tools for water system management
Features
Read full description

Next Generation Water Science makes water (and the people who maintain it) look great. Next Generation Water Science makes eco-friendly water treatments for pools, spas, industrial and agricultural water systems. All products are NSF/ANSI Certified for purity and safety. Through education and helpful tools like this mobile app, Next Generation Water Science has helped people of all aptitudes manage water better.

About

Doc Scan:OCR and PDF Scanner

This app acts as a smart scanning assistant, converting documents and images into editable text and PDFs. It offers features like OCR text recognition, ID card scanning, and photo translation, simplifying manual input and typesetting for students and office workers.

Highlights
  • Document scanning
  • OCR text recognition
  • ID card scanning
  • Photo translation
  • Image to Word conversion
  • PDF conversion
Features
Read full description

Scanner Almighty King is a smart scanning assistant tool that is convenient for students and office workers. Functions such as OCR text recognition, photo extraction scanning, image conversion to word, ID card scanning, photo translation, PDF conversion, etc., can be easily handled by Scanner Almighty King with one APP, eliminating the trouble of manual input and typesetting, high-definition image processing, and can be directly generated The electronic version is convenient, quick, clear and easy to use. ●Document scanning Use image processing algorithms to scan and manage your documents. ●Text recognition OCR text recognition, one-click text recognition. ● ID card scanning High-definition scanning of various documents, mobile scanner, 1:1 restoration of document printing, one-click stitching to A4 paper. ●Photograph translation Supports OCR recognition of most languages such as Chinese, English, Japanese, Korean, French, German, Russian, Spanish, etc., and fast translation. ●Image to Word Quickly and intelligently identify pictures, and convert word documents with one click, which is convenient and fast. ●Examination paper erasure Quickly erase the traces of the test paper and restore the original appearance of the test paper. ●receipt recognition Accurately identify the contents of receipts, making it easy to make electronic receipts. ●Business card recognition Accurate identification, standardized API output. ●PDF Converter One-click format conversion makes editing easier. ---------------------------------------- 【Automatic Renewal Terms】 There are three subscription options for premium accounts: Weekly membership: only $9.99/week Annual membership: only $29.99/year Lifetime membership: only $39.99 ● Subscription payment will be charged to your iTunes account at confirmation of purchase and at the beginning of each renewal period ● Renewal: The Apple iTunes account will be debited within 24 hours before the expiration, and the subscription period will be extended by one subscription period after the deduction is successful. ● Cancel Renewal: You may cancel your subscription or trial at any time by going to your iTunes account settings and canceling the subscription, otherwise it will automatically renew. This must be done 24 hours before the end of the trial period or any subscription period to avoid being charged. Subscriptions that include a trial period will automatically renew to a paid subscription. ● Subscriptions may be managed by the user and auto-renewal may be turned off by going to the user's Account Settings after purchase ● When you purchase a premium subscription during a trial period, any unused portion of the trial period, if offered, will forfeit. ●Privacy Policy: http://static.rhinoxlab.com/html/privacy/saomiaoyiwannengwang_bodi_en.html?appName=DocScan ●Member Payment Agreement: http://static.rhinoxlab.com/html/paymentagreement/general.html

Screenshots

LSI Calculator3 screens
Doc Scan:OCR and PDF Scanner4 screens

Verdict

The call

The clearest difference is review sentiment: LSI Calculator at 100% against Doc Scan:OCR and PDF Scanner's 15%. LSI Calculator also leads on rating (4.4 vs 3.5) and in-app purchases (none vs 8). On price, ratings volume, update cadence and ads there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Doc Scan:OCR and PDF Scanner sells 8 in-app purchases, starting at $4.99 per 7 days. LSI Calculator asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

LSI Calculator holds the better App Store score, 4.4 against 3.5. Both are backed by a comparable volume of ratings — 5 and 8 respectively. Written reviews point the same way: 100% of LSI Calculator's written reviews are positive against 15% of Doc Scan:OCR and PDF Scanner's.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 2 months. The most recent releases landed on June 11, 2026 and September 21, 2026 respectively.

Scorecard5 real differences · 5 level
LSI Calculator versus Doc Scan:OCR and PDF Scanner: the parameters behind the verdict, then further details
ParameterLSI CalculatorDoc Scan:OCR and PDF Scanner
PriceFreeFree
Rating4.4 (5 ratings) — better3.5 (8 ratings)
Positive reviews100.0% of reviews — better15.4% of reviews
Number of ratings58 — better
Update frequencyEvery 2 monthsEvery 2 months
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS11.0 — better15.6
Further details — not scored
Size52 MB72 MB
Age rating12+4+
DeveloperPure Planet Science & Technology, Inc.Hangzhou Jiadi Bozhong

Customer experience

LSI Calculator

All ratings5 ratings
Positive80.0%
Neutral0.0%
Negative20.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Doc Scan:OCR and PDF Scanner

All ratings8 ratings
Positive62.5%
Neutral0.0%
Negative37.5%
Written reviews13 reviews
Positive15.4%
Neutral0.0%
Negative84.6%

In-app purchases

None

LSI Calculator

No in-app purchases

8 purchases

Doc Scan:OCR and PDF Scanner

Subscriptions5
  • 扫描仪全能王-周会员7 Days trial$4.997 Days
  • monthly member$6.991 Month
  • weekly member$9.997 Days
Show 2 more
  • one-year member$29.991 Year
  • Quarterly member$39.993 Months
One-time3
  • 一个月高级版$2.99
  • 三个月vip$5.99
  • 永久会员$39.99

Questions

Is LSI Calculator free?
LSI Calculator is free to download, with no in-app purchases.
Is Doc Scan:OCR and PDF Scanner free?
Doc Scan:OCR and PDF Scanner is free to download, with in-app purchases available.
Which has better reviews, LSI Calculator or Doc Scan:OCR and PDF Scanner?
LSI Calculator is rated higher. LSI Calculator averages 4.4 out of 5 from 5 ratings, while Doc Scan:OCR and PDF Scanner averages 3.5 from 8 ratings.
Do LSI Calculator or Doc Scan:OCR and PDF Scanner have ads?
Neither LSI Calculator nor Doc Scan:OCR and PDF Scanner shows ads.
Which is updated more often, LSI Calculator or Doc Scan:OCR and PDF Scanner?
LSI Calculator ships an update every 2 months, and Doc Scan:OCR and PDF Scanner every 2 months. Most recently, LSI Calculator was updated on June 11, 2026 and Doc Scan:OCR and PDF Scanner on September 21, 2026.

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