Comparison

Piazza vs Codon

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

Head to head
About

Piazza

This platform facilitates communication and learning for higher education. Students can ask and answer questions, while instructors can monitor student engagement. It provides real-time updates and a centralized space for class interactions.

Highlights
  • Ask and answer questions
  • Real-time updates
  • Centralized class communication
  • Student engagement monitoring
  • Mobile access for students and instructors
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Piazza is the leading social learning platform for higher education, used by hundreds of thousands of students and more than 15 thousand professors for centralized class communications and polling. If you're a student, the Piazza app lets you ask and answer questions in all your Piazza classes from your mobile device, and updates you in real time when your peers are engaged. If you're an instructor, the app gives you a simple way to check in on your students during those spare moments between meetings. Stay connected to your class with Piazza!

About

Codon

Master biology from molecules to ecosystems with a comprehensive, offline curriculum. Explore 100 lessons, researcher profiles, and landmark experiments. Learn mechanisms and track progress with spaced repetition and interactive quizzes.

Highlights
  • Offline biology curriculum
  • 100 lessons with narration
  • Researcher profiles
  • Interactive quizzes with explanations
  • Spaced repetition learning
  • Offline access, no account needed
  • Home screen widgets
Features
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A four-year biology curriculum, offline, with no account and no network. Codon covers what an introductory sequence and the first two years of a degree teach: molecules and cells first, then inheritance and molecular biology, then evolution, diversity and ecology, then whole organisms and physiology. WHAT IS INSIDE 100 lessons across four years, each 15 to 25 minutes, with on-device narration 60 researcher profiles, from Mendel and Darwin to McClintock and Doudna 735 glossary terms, cross-linked to the lessons that use them 20 quizzes with worked explanations for every answer 18 landmark experiments reconstructed: Meselson and Stahl, Hershey and Chase, Luria and Delbruck Spaced repetition that schedules the terms you keep forgetting Bookmarks and notes on any lesson, profile or term Three Home Screen widgets: a quote, a term and a figure, each changing daily HOW IT TEACHES The course teaches mechanisms rather than vocabulary. Where a textbook says respiration yields 38 ATP, this one gives the real figure of roughly 30 to 32 and explains why the number moved. Where the field is unsettled, such as the origin of eukaryotes or the tempo of speciation, the lesson gives the competing accounts and who holds them. FREE AND PAID The first ten lessons are free. One purchase of $9.99 unlocks the remaining 90 and everything else, permanently. There is no subscription, there are no ads, and there is no account to create. Family Sharing is supported. OFFLINE BY DESIGN The app makes no network connections. Every lesson, profile, glossary entry, quiz and case study is bundled in the download, so the whole course works in airplane mode. Nothing you read or write here leaves your device.

Screenshots

Piazza3 screens
Codon3 screens

Verdict

The call

The clearest difference is rating: Codon at 5.0 against Piazza's 2.1. Piazza's advantage is in-app purchases (none vs 1) and ratings volume (279 vs 1). On price, update cadence, ads and device support 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. Codon sells 1 one-off in-app purchase. Piazza asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Codon holds the better App Store score, 5.0 against 2.1. That said, the two scores are not equally well evidenced: Piazza has 279 ratings behind it against 1, so its average is the more settled of the two.

UpkeepUpdate frequency

Piazza ships an update fortnightly, Codon every 10 days. The most recent releases landed on September 30, 2026 and September 22, 2026 respectively.

Scorecard5 real differences · 5 level
Piazza versus Codon: the parameters behind the verdict, then further details
ParameterPiazzaCodon
PriceFreeFree
Rating2.1 (279 ratings)5.0 (1 ratings) — better
Positive reviews14.2% of reviews—
Number of ratings279 — better1
Update frequencyFortnightlyEvery 10 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.6 — better17.0
Further details — not scored
Size3 MB5 MB
Age rating4+12+
DeveloperPiazza Technologies, Inc.OMAR DANIEL GRAZIANO

Customer experience

Piazza

All ratings279 ratings
Positive20.8%
Neutral10.0%
Negative69.2%
Written reviews113 reviews
Positive14.2%
Neutral11.5%
Negative74.3%

Codon

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

Bugs and requests

Piazza

Reported bugs

4 issues
  • Inability to post or reply
  • Randomly logs out users
  • Fails to load posts and resources
  • Incompatible with newer iOS versions

Requested features

5 requests
  • Dark mode option
  • Ability to access course materials
  • Improved formatting and editing tools
  • Better organization of posts and discussions
  • Seamless integration with web version

Codon

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

Piazza

No in-app purchases

1 purchases

Codon

One-time1
  • Codon Full Access$9.99

Questions

Is Piazza free?
Piazza is free to download, with no in-app purchases.
Is Codon free?
Codon is free to download, with in-app purchases available.
Which has better reviews, Piazza or Codon?
Codon is rated higher. Piazza averages 2.1 out of 5 from 279 ratings, while Codon averages 5.0 from 1 ratings.
Do Piazza or Codon have ads?
Neither Piazza nor Codon shows ads.
Which is updated more often, Piazza or Codon?
Piazza ships an update fortnightly, and Codon every 10 days. Most recently, Piazza was updated on September 30, 2026 and Codon on September 22, 2026.

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