ReactionFlash vs Chem_Calculator
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
ReactionFlash
This app serves as a comprehensive flashcard-style learning tool for named chemical reactions. It provides detailed information on reaction mechanisms and examples from scientific literature, with a quiz mode to test user knowledge.
- Learn named chemical reactions
- Understand reaction mechanisms
- View literature examples
- Quiz mode for knowledge testing
- Flashcard interface
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Want to refresh your memory on named chemical reactions before an exam or a group meeting? Get all the details with ReactionFlash(R) as a great way to learn named reactions, understand their mechanisms and view examples published in peer-reviewed literature. Designed and developed in consultation with Professor Dr. Erick M. Carreira of ETH Zürich, the app covers 1'266 named chemical reactions, by far the largest collection of Named Reactions. Professor Carreira has helped ensure that we have all the fundamental reactions that should be part of every chemist’s toolkit: from the best-known ones to the ones only Nobel Prize winners remember! The app is designed like a set of flash cards so it can be used as a learning tool as well as a reference. Each ‘card’ shows the reaction, its mechanism and examples from peer-reviewed, published literature. It also has a quiz mode that lets you test your knowledge. Linking into Reaxys enables you to find the most recent examples of each reaction, many with experimental details. Reaxys delivers experimental facts from the literature, enabling researchers to find the best synthetic routes and conditions. Find out more at https://www.elsevier.com/solutions/reaxys Download the app now and see if you know all the named reactions! Summary: - Learn named reactions - Review and understand mechanisms - Explore examples published in peer-reviewed literature - Take the ReactionFlash quiz and see how much you know If you need support, please contact us at reactionflash@elsevier.com. Reaxys and ReactionFlash are trade marks of Elsevier Limited, used under license.
Chem_Calculator
This app provides organic chemists with a molecular weight calculator featuring a full-sized periodic table. It allows for real-time calculation with mixed input of elements, numbers, and parentheses, and enables saving, editing, and deleting results.
- Molecular weight calculation
- Full-sized periodic table
- Real-time results
- Save, edit, and delete calculations
- Element detail lookup
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All organic chemists should have, best calculator for molecular weight in App Store! - check element detail by long pressing element button - elements, numbers, parenthesis mixed input, real-time result - full-sized periodic table, period 1, 2, 3 elements were combined in one line - save, delete or edit your result - more features on the way...
Screenshots
Verdict
The clearest difference is rating: ReactionFlash at 4.8 against Chem_Calculator's 4.3. ReactionFlash also leads on review sentiment (81% vs 50%). Chem_Calculator's advantage is ratings volume (156 vs 42) and iOS requirement (10.0 vs 14.0). On price, update cadence, ads and in-app purchases 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
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
ReactionFlash holds the better App Store score, 4.8 against 4.3. Both are backed by a comparable volume of ratings — 42 and 156 respectively. Written reviews point the same way: 81% of ReactionFlash's written reviews are positive against 50% of Chem_Calculator's.
Both ship on a similar rhythm, roughly every 4 months. The most recent releases landed on October 23, 2026 and October 29, 2026 respectively.
| Parameter | ReactionFlash | Chem_Calculator |
|---|---|---|
| Price | Free | Free |
| Rating | 4.8 (42 ratings) — better | 4.3 (156 ratings) |
| Positive reviews | 80.6% of reviews — better | 50.0% of reviews |
| Number of ratings | 42 | 156 — better |
| Update frequency | Every 4 months | Every 4 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | Free |
| Devices | iPhone, iPod | iPhone, iPad, iPod — better |
| Requires iOS | 14.0 | 10.0 — better |
| Further details — not scored | ||
| Size | 37 MB | 34 MB |
| Age rating | 4+ | 4+ |
| Developer | Elsevier Limited | 铠宁 雷 |
Customer experience
ReactionFlash
Chem_Calculator
In-app purchases
ReactionFlash
No in-app purchases
Chem_Calculator
No in-app purchases
Questions
Is ReactionFlash free?
Is Chem_Calculator free?
Which has better reviews, ReactionFlash or Chem_Calculator?
Do ReactionFlash or Chem_Calculator have ads?
Which is updated more often, ReactionFlash or Chem_Calculator?
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