Trigonometry Quick Reference vs 555 Timer & Oscillators Pro
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Trigonometry Quick Reference
This app offers a concise overview of fundamental trigonometry concepts, including sine, cosine, tangent, and inverse functions. It serves as a quick reference tool for students to review key ideas and test their understanding with quizzes.
- Overview of basic trigonometry concepts
- Explanations of sine, cosine, and tangent
- Information on inverse functions
- Unit circle, ranges, and domains
- Quizzes to measure understanding
- Detailed explanations on key topics
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Trigonometry Quick Reference provides an overview of the basic concepts needed for success in trigonometry. It provides a simple way to access and review the fundamental ideas of Trigonometry. After studying the information on one of the screens students can take a quiz to measure their understanding. Here are a few of the ways you will use Trigonometry Quick Reference everyday with your students: • Use Trigonometry Quick Reference as an informational tool to help students understand and review basic concepts of trigonometry, including the meaning and application of sine, cosine, and tangent functions, inverse functions, the unit circuit, ranges and domains. •Tap the areas of the screen to bring up more detailed information and explanations about essential trigonometry concepts. •Tap to get more information about key topics including trigonometric functions, trigonometric laws, inverse function, periodic formulas, tangent and cotangent identities, sum and difference formulas and many other key concepts.
555 Timer & Oscillators Pro
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Master the design of oscillators and waveform generators using 555 timer integrated circuits, digital logic integrated circuits, operational amplifiers, and transistors. The application provides a comprehensive collection of over 130 tutorials and circuit diagrams, covering 555 timer circuits and practical applications, CMOS 4000 series logic oscillators, TTL 74LS and 74HC series oscillators, operational amplifier–based waveform generators, and transistor multivibrators. Designed for electronics beginners, students, hobbyists, and professional engineers, the app serves as a complete reference and learning tool for designing, understanding, and building oscillators, multivibrators, pulse generators, and waveform circuits commonly used in both analog and digital electronics. In addition to tutorials and schematics, the app includes built-in calculators for frequency, timing, duty cycle, and component value estimation, helping users quickly calculate and adjust circuit parameters. All topics are presented with clear circuit diagrams and detailed explanations. Available in 14 Languages: • English, French, German, Indonesian, Italian, Japanese, Polish, Portuguese, Russian, Simplified Chinese, Spanish, Turkish, Ukrainian, and Vietnamese — study in your native language! Covered Topics: • 555 Timer IC Series • Astable, monostable, and bistable modes • Pulse Width Modulation (PWM) • Voltage conversion circuits • Sensor and external module interfacing • CMOS Logic Oscillators • CMOS 4000 series circuits • Astable, monostable, and bistable modes • Gated CMOS oscillators • TTL / HC Logic Oscillators • TTL 74LS series circuits • 74HC series logic oscillators • Astable and monostable modes • Operational Amplifier Oscillators • Sine wave generators • Square-wave pulse generators • Triangle wave generators • Transistor-Based Oscillators • Transistor-Based Astable multivibrators • Transistor-Based Monostable multivibrators The Pro edition provides additional tools for faster learning and easy navigation: • Full-text search across all lessons and components • Favorites for saving and organizing important topics The content is regularly updated and expanded with each new release, ensuring the latest tutorials and circuit examples are always available.
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Verdict
The clearest difference is price: Trigonometry Quick Reference at $0.99 against 555 Timer & Oscillators Pro's $4.99. Trigonometry Quick Reference also leads on iOS requirement (12.0 vs 16.0). 555 Timer & Oscillators Pro's advantage is update cadence (every 3 months vs every 8 months) and device support (3 vs 1). On 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
Trigonometry Quick Reference costs $0.99 and 555 Timer & Oscillators Pro $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Trigonometry Quick Reference ships an update every 8 months, 555 Timer & Oscillators Pro every 3 months. The most recent releases landed on June 8, 2026 and September 24, 2026 respectively.
| Parameter | Trigonometry Quick Reference | 555 Timer & Oscillators Pro |
|---|---|---|
| Price | $0.99 — better | $4.99 |
| Rating | 5.0 (1 ratings) — better | — |
| Positive reviews | 100.0% of reviews | — |
| Number of ratings | 1 — better | — |
| Update frequency | Every 8 months | Every 3 months — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | — |
| Devices | iPad | iPhone, iPad, Mac — better |
| Requires iOS | 12.0 — better | 16.0 |
| Further details — not scored | ||
| Size | 10 MB | 22 MB |
| Age rating | 4+ | 4+ |
| Developer | Ventura Educational Systems | ALG Software Lab |
In-app purchases
Trigonometry Quick Reference
No in-app purchases
555 Timer & Oscillators Pro
No in-app purchases
Questions
Is Trigonometry Quick Reference free?
Is 555 Timer & Oscillators Pro free?
Do Trigonometry Quick Reference or 555 Timer & Oscillators Pro have ads?
Which is updated more often, Trigonometry Quick Reference or 555 Timer & Oscillators Pro?
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