555 Calc vs NSYS Diagnostics
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.
NSYS Diagnostics
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NSYS Diagnostics is a professional training application designed to help users learn and practice correct interactions with device functions. The app provides guided scenarios that help users understand how device functions respond when the required actions are performed correctly. NSYS Diagnostics supports onboarding, training, and knowledge validation for workflows where correct interaction with device functions is required.
Screenshots
Verdict
The clearest difference is ads: NSYS Diagnostics at none against 555 Calc's shown. NSYS Diagnostics also leads on update cadence (monthly vs every 20 months). On price, in-app purchases, 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. Neither carries in-app purchases, so what you see is what you pay.
555 Calc ships an update every 20 months, NSYS Diagnostics monthly. The most recent releases landed on June 1, 2026 and September 22, 2026 respectively.
| Parameter | 555 Calc | NSYS Diagnostics |
|---|---|---|
| Price | Free | Free |
| Rating | 4.0 (3 ratings) — better | — |
| Positive reviews | 50.0% of reviews | — |
| Number of ratings | 3 — better | — |
| Update frequency | Every 20 months | Monthly — better |
| Ads | Yes | No — better |
| In-app purchases | No | No |
| Monetization | Ad-supported | — |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod, Apple Watch — better |
| Requires iOS | 11.0 — better | 12 |
| Further details — not scored | ||
| Size | 18 MB | 24 MB |
| Age rating | 4+ | 4+ |
| Developer | Jibiki Works | Grigoriy Glazman |
In-app purchases
555 Calc
No in-app purchases
NSYS Diagnostics
No in-app purchases
