Comparison

MolecuLens vs Big O Notation

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

Head to head
About

MolecuLens

Explore and learn about over 100 million chemical compounds in interactive 3D. AI-powered features generate guided tours, quizzes, and shareable diagrams to enhance understanding and communication.

Highlights
  • Interactive 2D/3D molecular viewing
  • AI-guided molecular tours and quizzes
  • Search by name, SMILES, formula, or drawing
  • Conformer generation
  • 3D orbital overlays (Pro feature)
  • High-quality diagram generation (Pro feature)
Features
Read full description

Explore molecules in 3D, learn chemistry faster, and generate shareable figures with help from AI. MolecuLens gives you access to 100M+ compounds from PubChem. Search by name, SMILES, formula, or even draw — then explore interactive 2D/3D structures in seconds. VISUALIZE & EXPLORE • Interactive 2D and 3D molecular viewing • Highlight functional groups, rings, and key regions with Lens mode • Native support for transition metal complexes (11 metals, 5+ geometries) • Conformer generation for molecules without existing 3D structures AI-POWERED LEARNING • Generate guided molecular tours with AI narration • Create quizzes grounded in molecular analytics • Turn structures into stories for teaching and communication SEARCH ANY WAY YOU WANT • Common names: "caffeine", "aspirin", "glucose" • SMILES strings: paste any valid structure • Coordination notation: "[Fe(H2O)6]3+" • Chemical formulas and PubChem CIDs BUILT FOR EDUCATION Great for organic chemistry students, biochem learners, educators, and science communicators. Build intuition by interacting with structures — not memorizing them. MolecuLens PRO (Auto-Renewable Subscription) Pro unlocks premium features including: • 3D orbital overlays (HOMO, LUMO, electron density) • Unlimited AI-guided molecular tours • Custom interactive quiz generation • High-quality molecular diagram generation Free trial and pricing • 7-day free trial (where available) • Monthly: $4.99/month • Annual: $24.99/year Payment is charged to your Apple ID account at confirmation of purchase. Subscription automatically renews unless canceled at least 24 hours before the end of the current period. Your account will be charged for renewal within 24 hours prior to the end of the current period. You can manage or cancel your subscription in Settings → Apple ID → Subscriptions. Privacy Policy: https://www.moleculens.com/privacy-policy Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

Big O Notation

Features
Read full description

Big O Notation is an independent study app for learning, reviewing, and practicing algorithm complexity. It is built for students, self-taught developers, coding interview candidates, and anyone who wants clearer intuition for time and space complexity. Study across Fundamentals, Practical Skills, Common Pitfalls, and Advanced Concepts with 160 focused questions. Every question includes an explanation so you can understand why an answer is right and where your reasoning went off track. Features: - FSRS spaced-repetition intervals for smarter review - Weak-point heatmap to spot topics that need attention - Daily challenge for steady practice - Mock exams for timed review - Offline practice - No login required Practice offline, no login required. Independent study app for Big O Notation practice. Not affiliated with, endorsed by, or sponsored by any company, certification body, exam operator, or vendor. All trademarks belong to their respective owners.

Screenshots

MolecuLens4 screens
Big O Notation4 screens

Verdict

The call

The clearest difference is in-app purchases: Big O Notation at none against MolecuLens's 2. On price, ads, device support and iOS requirement 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. MolecuLens sells 2 in-app purchases, starting at $4.99 per month. Big O Notation asks for nothing beyond the download.

Scorecard1 real difference · 9 level
MolecuLens versus Big O Notation: the parameters behind the verdict, then further details
ParameterMolecuLensBig O Notation
PriceFreeFree
Rating5.0 (3 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings3 — better—
Update frequencyMonthly—
AdsNoNo
In-app purchasesYesNo — better
MonetizationFreemium—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.115.1
Further details — not scored
Size43 MB38 MB
Age rating4+4+
DeveloperJake KinchenAFTW LLC

In-app purchases

2 purchases

MolecuLens

Subscriptions2
  • MolecuLens Pro (Monthly)7 Days trial$4.991 Month
  • MolecuLens Pro (Yearly)7 Days trial$24.991 Year
None

Big O Notation

No in-app purchases

Questions

Is MolecuLens free?
MolecuLens is free to download, with in-app purchases available.
Is Big O Notation free?
Big O Notation is free to download, with no in-app purchases.
Do MolecuLens or Big O Notation have ads?
Neither MolecuLens nor Big O Notation shows ads.

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