Comparison

ZipGrade vs World History Slots

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

Head to head
About

ZipGrade

Instantly grade multiple-choice tests and quizzes using your device's camera. This app offers a fast and accurate way for educators to assess student work, with features for organizing and exporting results. It provides immediate feedback to inform lesson planning and assignments.

Highlights
  • Instant grading with device camera
  • Supports multiple choice tests and quizzes
  • Organizes and exports results (PDF, Excel)
  • Free answer sheet templates available
  • Companion website for data management
  • Stores results by student, subject, and quiz
Features
Read full description

Teachers can grade multiple choice tests, quizzes, and assessments instantly in the classroom by using their iPhone or iPad's camera as a scanner. It is the most cost effective, fastest, and most accurate way to grade tests in the classroom or where ever you are. -------------------------------------------------------- * Free answer sheets available in several formats and sizes up to 100 questions (including custom form wizard) * Organizes results for reporting and exporting via PDF and Excel-readable format * Uses student ID numbers or written name of student for reporting. * Use companion website (www.zipgrade.com) to manage your data and upload student lists and review results in dozens of reports and exports. -------------------------------------------------------- Use for exit tickets, formative assessments, or regular quizzes. Stores results by students, subject, and quiz. By giving teachers the flexibility to grade papers instantly anywhere, ZipGrade provides immediate feedback on current knowledge and can be used to better focus lessons and assignments. Download ZipGrade free with access to all features and website, but limited to 100 scans per month. After you've used it for a class or two, use the in-app purchase a non-recurring subscription with unlimited scanning.

About

World History Slots

This app transforms AP World History study into a daily practice game. Spin reels to generate historical prompts and recall evidence before a timer runs out. Premium features offer AI-graded Short Answer Questions with instant feedback.

Highlights
  • Daily practice habit formation
  • Randomized era, region, theme prompts
  • Timed recall of historical evidence
  • AI-graded Short Answer Questions
  • Instant feedback scored to AP rubric
  • Progress tracking and awards
Features
Read full description

World History Slots — AP World History Exam Prep World History Slots turns AP World History study into an active, daily practice habit — built by an AP World teacher for AP World students. It's completely free, with no ads and no subscription. HOW IT WORKS - Spin the reels to generate a random combination of AP World History era, region, and theme. Try to recall specific historical evidence before the timer ends — just like thinking on your feet during the actual exam. Then check your work with curated key terms and an overview for that exact combination, and grade your own recall. REVIEW ALL YEAR - You don't have to wait until spring. Choose the eras you've covered in class so far, and add more as the year goes on. You can also filter by region and theme to focus on what you need most. 216 COMBINATIONS - Every era, region, and theme combination has its own study suggestions, written to match the AP World History course. BUILD THE HABIT - Ten spins a day keeps your streak alive. See how you did today and yesterday, and come back tomorrow. AP® and College Board® are registered trademarks of the College Board, which is not affiliated with, and does not endorse, this app. Privacy Policy: https://mistercorbett.com/#privacy-whap Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

ZipGrade3 screens
World History Slots4 screens

Verdict

The call

The clearest difference is update cadence: World History Slots at every 5 days against ZipGrade's every 6 weeks. ZipGrade's advantage is rating (4.9 vs 4.5) and ratings volume (37K vs 4). On price, ads, in-app purchases and monetization model 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. ZipGrade sells 1 one-off in-app purchase and World History Slots sells 3 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

ZipGrade holds the better App Store score, 4.9 against 4.5. That said, the two scores are not equally well evidenced: ZipGrade has 37K ratings behind it against 4, so its average is the more settled of the two.

UpkeepUpdate frequency

ZipGrade ships an update every 6 weeks, World History Slots every 5 days. The most recent releases landed on November 9, 2026 and November 5, 2026 respectively.

Scorecard4 real differences · 6 level
ZipGrade versus World History Slots: the parameters behind the verdict, then further details
ParameterZipGradeWorld History Slots
PriceFreeFree
Rating4.9 (37K ratings) — better4.5 (4 ratings)
Positive reviews85.9% of reviews—
Number of ratings37K — better4
Update frequencyEvery 6 weeksEvery 5 days — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFreemium
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS13.0 — better26.2
Further details — not scored
Size30 MB5 MB
Age rating4+4+
DeveloperZipGrade LLCBRIAN JAMES CORBETT

Customer experience

ZipGrade

All ratings36,274 ratings
Positive98.3%
Neutral0.9%
Negative0.9%
Written reviews510 reviews
Positive85.9%
Neutral3.1%
Negative11.0%

World History Slots

All ratings4 ratings
Positive75.0%
Neutral25.0%
Negative0.0%

Bugs and requests

ZipGrade

Reported bugs

2 issues
  • Scanning issues with flat surface detection
  • Incorrect answer marking due to eraser marks

Requested features

4 requests
  • Ability to change question point values in bulk
  • Option to create/edit answer keys on website
  • Support for non-multiple choice question types
  • Improved data export/integration with other systems

World History Slots

Not enough reviews yet to summarise bugs or requests.

In-app purchases

1 purchases

ZipGrade

One-time1
  • Add 1 year of use$6.99
3 purchases

World History Slots

Subscriptions3
  • Basic$2.991 Month
  • Standard$4.991 Month
  • AP Ready$8.991 Month

Questions

Is ZipGrade free?
ZipGrade is free to download, with in-app purchases available.
Is World History Slots free?
World History Slots is free to download, with in-app purchases available.
Which has better reviews, ZipGrade or World History Slots?
ZipGrade is rated higher. ZipGrade averages 4.9 out of 5 from 37K ratings, while World History Slots averages 4.5 from 4 ratings.
Do ZipGrade or World History Slots have ads?
Neither ZipGrade nor World History Slots shows ads.
Which is updated more often, ZipGrade or World History Slots?
ZipGrade ships an update every 6 weeks, and World History Slots every 5 days. Most recently, ZipGrade was updated on November 9, 2026 and World History Slots on November 5, 2026.

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