Combinatorics Calculator vs ReadBay
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Combinatorics Calculator
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Finish your homework instantly. Prepare for exams without stress. Free, complete step-by-step solutions. Enter your values and calculate permutations, combinations, and variations – with and without repetition. HOW IT WORKS Enter your values in the correct fields and get started. You’ll receive the solution instantly and can share it with friends or classmates. YOUR PERSONAL DATA We don’t need it. Only anonymized data is collected, for example: - which features are used - how many solutions are generated This helps us improve. We cannot identify you. COSTS Everything is free to use. 24/7 access to your solutions. All solution steps are always complete. If you need many solutions in a short time, additional purchase options are available. EXTRAS - curated learning videos - feedback on incorrect inputs - manage your own solutions - app introduction CONTACT Questions or feedback via Discord or directly in the app review.
ReadBay
Access concise summaries and audio versions of bestselling books in under 15 minutes. Master key insights from business, self-help, and personal development titles for faster learning and habit building.
- 15-minute book summaries
- Audiobook summaries
- Offline reading
- Progress tracking
- Habit building challenges
- Bookmark favorite notes
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Book Summary & Audiobook App - Learn in 15 Minutes Master key insights from bestselling self help, business books, and personal development titles with ReadBay's quick book summaries! Our speed reading approach delivers professional development content faster than Blinkist or Headway. Why ReadBay Beats the Competition: 15 minute reads - Perfect for daily learning Audiobook summaries for hands-free motivation Offline reading - Learn anywhere, anytime Productivity tools with progress tracking Habit building challenges and goals Popular Categories: Leadership books, Business books, Self Help, Productivity, Psychology, Money & Investing, Professional development, Communication Perfect for Quick Book Summaries: Busy professionals seeking key insights Students wanting speed reading solutions Anyone building daily learning habits Commuters maximizing time with audiobook content Smart Learning Features: Bookmark favorite book notes Set habit building challenges Learn faster with audio mode Motivation through progress tracking Start your learning journey with FREE book summaries! Website: https://www.growthmindapps.com Terms: https://www.growthmindapps.com/terms Privacy: https://www.growthmindapps.com/privacy
Screenshots
Verdict
Combinatorics Calculator and ReadBay are too close to call on the numbers: across 6 compared parameters — price, update cadence, ads and in-app purchases among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Combinatorics Calculator sells 8 one-off in-app purchases and ReadBay sells 4 in-app purchases, starting at $4.99 per month. Whichever you choose, the download price is not the number that matters.
Combinatorics Calculator ships an update every 3 weeks, ReadBay every 10 days. The most recent releases landed on October 24, 2026 and October 23, 2026 respectively.
| Parameter | Combinatorics Calculator | ReadBay |
|---|---|---|
| Price | Free | Free |
| Rating | — | 4.8 (239 ratings) — better |
| Positive reviews | — | 84.5% of reviews |
| Number of ratings | — | 239 — better |
| Update frequency | Every 3 weeks | Every 10 days — better |
| Ads | No | No |
| In-app purchases | Yes | Yes |
| Monetization | — | Free with in-app purchases |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 15.0 — better | 15.1 |
| Further details — not scored | ||
| Size | 180 MB | 60 MB |
| Age rating | 4+ | 17+ |
| Developer | Glindemann, Sennoun, Langer GbR | Bange Sabastine Hwonyi |
Bugs and requests
Combinatorics Calculator
Not enough reviews yet to summarise bugs or requests.
ReadBay
Reported bugs
2 issues- Purchased lifetime subscription not accessible on new device
- Identical summaries for different books
Requested features
3 requests- Support for French books
- Ability to share summaries to Kindle
- More language options (e.g., Chinese)
In-app purchases
Combinatorics Calculator
- +30 User Tokens$0.29
- +1 Convenience Token / 6h, max. +2$0.59
- +2 Convenience Tokens / 6h, max. +4$0.99
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- +150 User Tokens$0.99
- +300 User Tokens$1.49
- +4 Convenience Tokens / 6h, max. +8$1.59
- Lifetime Access$1.99
- Remove Ads$1.99
ReadBay
- Monthly Pro Membership$4.991 Month
- Pro Annual Membership$19.991 Year
- Yearly Pro Membership3 Days trial$24.991 Year
- Lifetime Membership$39.99
Questions
Is Combinatorics Calculator free?
Is ReadBay free?
Do Combinatorics Calculator or ReadBay have ads?
Which is updated more often, Combinatorics Calculator or ReadBay?
Other comparisons
