Comparison

LeetCode vs Rex

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

Head to head
About

LeetCode

Practice coding challenges and prepare for technical interviews on the go. Discover company-specific questions, manage your practice lists, and track your progress. Stay updated with contests and daily quests to improve your skills.

Highlights
  • Search and discover company questions
  • Practice coding challenges
  • Manage practice lists
  • Track personal progress
  • Contest registration and calendar sync
  • Daily challenges and quests
Features
Read full description

One LeetCode a day keeps your reasoning in play. Introducing LeetCode for iOS and iPadOS. Enjoy LeetCoding right at your fingertips — jump in for quick practice, browse your collections, and stay on top of important events and progress. With LeetCode in the palm of your hand, you can easily: • Search and discover the latest company questions. • View and quickly practice your favorite challenges right in the palm of your hand. • Manage your lists or add to your wishlist to practice later. • Keep track of your personal progress with a rich profile view and widgets. • Stay notified and keep your streak alive — level up with new challenges and quests every day. • Register for contests and sync them to your calendar. Live Activities keep you updated on contest progress — so you never miss a moment. • And more content and features coming every month… Terms of Services: https://leetcode.com/terms/ Privacy Policy: https://leetcode.com/privacy/

About

Rex

This app offers an interactive learning experience by explaining concepts aloud and allowing users to manipulate 3D models and live charts. It consolidates notes, PDFs, and web research onto a single canvas and supports collaborative study sessions.

Highlights
  • Voice explanations of questions
  • Interactive 3D scenes and live charts
  • Consolidated study canvas
  • Lecture transcription and note-taking
  • Read-aloud functionality for notes and PDFs
  • Language practice with real scenes
  • Live collaborative study boards
Read full description

Rex is a study companion that teaches out loud. Ask a question and hear it explained on a board you can draw on, pull apart, and keep. Most study apps hand you more text to read. Rex shows you the thing itself: a heart mid-beat, a cell you can fly into, a physics problem you can grab and change while it runs. ASK, AND ACTUALLY UNDERSTAND Type or speak a question and get a clear explanation built onto the board in front of you, not buried in a chat log. Ask about what is already on your board and Rex can see it. ONE BOARD FOR THE WHOLE CLASS Notes, PDFs, drawings, timers, recordings, graphs, checklists and web research sit side by side on one canvas. Stop switching between five apps to study one subject. 3D SCENES AND LIVE CHARTS Explore over 70 interactive charts and 20 explorable 3D scenes across biology, physics, chemistry, earth science and computing. Zoom from a whole body down to a single molecule. Change the inputs and watch what happens. RECORD THE LECTURE, GET THE NOTES Rex transcribes while you record, so your notes write themselves. LISTEN INSTEAD OF READING Any note, PDF or scanned page can be read aloud in a natural voice, each sentence highlighted as it is spoken. Photographed pages work too. SPEAK A NEW LANGUAGE Practise in twenty languages by walking through real scenes and talking with characters who answer back. STUDY TOGETHER Share a board and work on it live with classmates. FREE TO START The whiteboard and the core study tools are free. SUBSCRIPTIONS Pro, $11.99 per month. Pro Annual, $99.99 per year, which is about 36 percent less than paying monthly. Premium AI features, higher daily limits, class memory that persists between sessions, premium voice, study video generation and live board sharing require an auto-renewing Pro subscription. Prices are charged from day one and there is no free trial. Payment is charged to your Apple ID at confirmation of purchase. Subscriptions renew automatically unless cancelled at least 24 hours before the end of the current period, and your account is charged for renewal within 24 hours of the end of the current period. Manage or cancel in your App Store account settings. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://rexstudyapp.com/privacy.html

Screenshots

LeetCode4 screens
Rex4 screens

Verdict

The call

The clearest difference is ratings volume: LeetCode at 626 against Rex's 1. LeetCode also leads on monetization model (ad-supported vs free with in-app purchases) and iOS requirement (16.0 vs 18.6). Rex's advantage is update cadence (every 4 days vs fortnightly) and rating (5.0 vs 4.8). On price, ads, in-app purchases 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. LeetCode sells 2 in-app purchases, starting at $35.00 per month and Rex sells 2 in-app purchases, starting at $11.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Rex holds the better App Store score, 5.0 against 4.8. That said, the two scores are not equally well evidenced: LeetCode has 626 ratings behind it against 1, so its average is the more settled of the two.

UpkeepUpdate frequency

LeetCode ships an update fortnightly, Rex every 4 days. The most recent releases landed on October 19, 2026 and October 9, 2026 respectively.

Scorecard5 real differences · 5 level
LeetCode versus Rex: the parameters behind the verdict, then further details
ParameterLeetCodeRex
PriceFreeFree
Rating4.8 (626 ratings)5.0 (1 ratings) — better
Positive reviews44.2% of reviews—
Number of ratings626 — better1
Update frequencyFortnightlyEvery 4 days — better
AdsNoNo
In-app purchasesYesYes
MonetizationAd-supported — betterFree with in-app purchases
DevicesiPhone, iPadiPhone, iPad, Mac — better
Requires iOS16.0 — better18.6
Further details — not scored
Size110 MB80 MB
Age rating4+12+
DeveloperLeetCodeOran Egbuchunam

Customer experience

LeetCode

All ratings626 ratings
Positive93.6%
Neutral2.2%
Negative4.2%
Written reviews52 reviews
Positive44.2%
Neutral28.8%
Negative26.9%

Rex

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

In-app purchases

2 purchases

LeetCode

Subscriptions2
  • LeetCode Premium Monthly$35.001 Month
  • LeetCode Premium Yearly$159.001 Year
2 purchases

Rex

Subscriptions2
  • Pro$11.991 Month
  • Rex Pro Annual$99.991 Year

Questions

Is LeetCode free?
LeetCode is free to download, with in-app purchases available.
Is Rex free?
Rex is free to download, with in-app purchases available.
Which has better reviews, LeetCode or Rex?
Rex is rated higher. LeetCode averages 4.8 out of 5 from 626 ratings, while Rex averages 5.0 from 1 ratings.
Do LeetCode or Rex have ads?
Neither LeetCode nor Rex shows ads.
Which is updated more often, LeetCode or Rex?
LeetCode ships an update fortnightly, and Rex every 4 days. Most recently, LeetCode was updated on October 19, 2026 and Rex on October 9, 2026.

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