555 Calc vs 8051 Tutorial
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
555 Calc
This utility app helps engineers and hobbyists calculate resistor values for circuits using the Timer IC 555. Simply input frequency, duty ratio, and capacitor values to get the required resistor outputs.
- Calculate resistor values
- Input frequency
- Input duty ratio
- Input capacitor value
- Timer IC 555 circuit design
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This App calculates registors value, when designing the circuit using Timer IC 555. How to (1) Input Frequency value. (2) Input Duty Ratio. (3) Input C1 Value. (4) Touch ‘Calculate’ button. (5) Registors value will be displayed. Note. * Set Duty Ratio to 50 ~ 99. * If you set Duty Ratio to 50, R1 value will be set to 0.
8051 Tutorial
Learn 8051 microcontroller programming in C with this comprehensive tutorial. It covers architecture, assembly, and C language, featuring 11 practical projects. An optional Pro version offers additional projects with source code and advanced features.
- 8051 architecture review
- 8051 assembly mnemonics
- 8051 C language programming
- 11 practical projects
- Baud calculator
- Pro version with extra projects and source code
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This app is a 8051 tutorial based on C language. It is suitable for hobbyist or engineering students. Features • 8051 architecture review • 8051 asm mnemonics • 8051 C language • 11 projects including LED, buzzer, key switch, external interrupt, 7-segment display, 8x8 led matrix, timer (mode 0,1 ) • Baud calculator Features in Pro • Extra 11 projects with source code • Projects with complete uVision project and document • Create C source code of timer mode 0,1,2 • Data pattern code generator of 8x8 LED matrix All product names, trademarks and registered trademarks are property of their respective owners. All company, product and service names used in this app are for identification purposes only. Use of these names, trademarks and brands does not imply endorsement.
Screenshots
Verdict
The clearest difference is rating: 8051 Tutorial at 5.0 against 555 Calc's 4.0. 8051 Tutorial also leads on ads (none vs shown) and update cadence (every 3 months vs every 20 months). 555 Calc's advantage is in-app purchases (none vs 10) and ratings volume (3 vs 1). On price, review sentiment, device support and iOS requirement 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. 8051 Tutorial sells 10 one-off in-app purchases. 555 Calc asks for nothing beyond the download.
8051 Tutorial holds the better App Store score, 5.0 against 4.0. Both are backed by a comparable volume of ratings — 3 and 1 respectively. Written reviews split almost evenly too, at 50% and 50% positive.
555 Calc ships an update every 20 months, 8051 Tutorial every 3 months. The most recent releases landed on June 1, 2026 and September 16, 2026 respectively.
| Parameter | 555 Calc | 8051 Tutorial |
|---|---|---|
| Price | Free | Free |
| Rating | 4.0 (3 ratings) | 5.0 (1 ratings) — better |
| Positive reviews | 50.0% of reviews | 50.0% of reviews |
| Number of ratings | 3 — better | 1 |
| Update frequency | Every 20 months | Every 3 months — better |
| Ads | Yes | No — better |
| In-app purchases | No — better | Yes |
| Monetization | Ad-supported — better | Free with in-app purchases |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 11.0 — better | 12.0 |
| Further details — not scored | ||
| Size | 18 MB | 17 MB |
| Age rating | 4+ | 4+ |
| Developer | Jibiki Works | Siu Yuen Ho |
Customer experience
555 Calc
8051 Tutorial
In-app purchases
555 Calc
No in-app purchases
8051 Tutorial
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