Comparison

RxMarbles vs Mockpit

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

Head to head
About

RxMarbles

Visualize and understand ReactiveX observable sequences with interactive diagrams. This educational tool helps developers grasp complex asynchronous programming concepts by illustrating event-based data streams and composition operators.

Highlights
  • Interactive observable diagrams
  • Visualization of event streams
  • Demonstration of composition operators
  • Educational tool for asynchronous programming
  • Explains observer pattern extensions
Features
Read full description

Interactive diagrams of Rx Observables. ReactiveX is a library for composing asynchronous and event-based programs by using observable sequences. It extends the observer pattern to support sequences of data and/or events and adds operators that allow you to compose sequences together declaratively while abstracting away concerns about things like low-level threading, synchronization, thread-safety, concurrent data structures, and non-blocking I/O.

About

Mockpit

Features
Read full description

Mockpit turns iOS and Swift interview prep into a daily habit that sticks. Practice with spaced-repetition flashcards, rehearse real mock interviews, solve Swift coding puzzles, and study a deep iOS knowledge base — all in one app built for developers getting ready for their next technical interview. Spaced-repetition flashcards 545 interview questions with concise answers, scheduled by a proven review algorithm so each card comes back right before you'd forget it. Rate how well you knew it and Mockpit plans the next review — undo a misgrade in one tap, and flag anything you didn't get for a focused "to review" queue. iOS knowledge base 120+ in-depth notes covering Swift Concurrency, SwiftUI, app architecture, multithreading, UIKit, the iOS SDK, testing and more. Notes link to each other, render code in monospace, and are searchable by title and text — read to understand, not just memorize. Mock interviews Practice by section — recruiter screen, Swift fundamentals, system design, algorithms and behavioral — for the companies you're actually interviewing with. Run a timed set of questions and review what you missed with links back to the relevant notes. Coding puzzles and a live sandbox Sharpen the parts real interviews test: "what prints?" output puzzles, memory-leak spotting and concurrency challenges. Write and run Swift in a built-in sandbox to check your reasoning on the spot. Interview tracker Add the companies you're pursuing, track every round from the recruiter call to the onsite, and get a reminder before each interview so nothing slips. Progress that keeps you going Build a daily streak, watch topics move toward mastery, see your weak areas by section, and unlock personal milestones as you go. Free & Pro Train with flashcards and preview the knowledge base for free. Mockpit Pro unlocks the full knowledge base, mock interviews, coding puzzles, the Swift sandbox and multi-language content. Start with a free 3-day trial. — Subscription details — Mockpit Pro is offered Monthly auto-renewable subscription includes a 3-day free trial. • Payment is charged to your Apple ID at confirmation of purchase. • A subscription renews automatically unless canceled at least 24 hours before the end of the current period. • Manage or cancel anytime in your App Store account settings. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

RxMarbles3 screens
Mockpit4 screens

Verdict

The call

The clearest difference is in-app purchases: RxMarbles at none against Mockpit's 4. RxMarbles also leads on ads (none vs shown) and iOS requirement (9.2 vs 18.0). Mockpit's advantage is update cadence (weekly vs every 4 months). On price 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. Mockpit sells 4 in-app purchases, starting at $4.99 per 7 days. RxMarbles asks for nothing beyond the download.

UpkeepUpdate frequency

RxMarbles ships an update every 4 months, Mockpit weekly. The most recent releases landed on October 7, 2026 and October 1, 2026 respectively.

Scorecard4 real differences · 6 level
RxMarbles versus Mockpit: the parameters behind the verdict, then further details
ParameterRxMarblesMockpit
PriceFreeFree
Rating4.9 (16 ratings) — better—
Positive reviews84.0% of reviews—
Number of ratings16 — better—
Update frequencyEvery 4 monthsWeekly — better
AdsNo — betterYes
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS9.2 — better18.0
Further details — not scored
Size21 MB13 MB
Age rating4+4+
DeveloperAnjLabAzizbek Ismailov

In-app purchases

None

RxMarbles

No in-app purchases

4 purchases

Mockpit

Subscriptions3
  • Mockpit Pro — Weekly$4.997 Days
  • Pro$14.991 Month
  • Mockpit Pro — Yearly3 Days trial$59.991 Year
One-time1
  • Sprint — 7 days$9.99

Questions

Is RxMarbles free?
RxMarbles is free to download, with no in-app purchases.
Is Mockpit free?
Mockpit is free to download, with in-app purchases available.
Do RxMarbles or Mockpit have ads?
Mockpit shows ads; RxMarbles does not.
Which is updated more often, RxMarbles or Mockpit?
RxMarbles ships an update every 4 months, and Mockpit weekly. Most recently, RxMarbles was updated on October 7, 2026 and Mockpit on October 1, 2026.

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