# Timer 555 Calculator Pro — user reviews

> 3 indexed App Store user reviews of Timer 555 Calculator Pro by Siu Yuen Ho, rated 4.70/5 from 3 ratings.

- Source: https://appshunter.io/ios/app/timer-555-calculator-pro/id833443125/reviews
- App overview in markdown: https://appshunter.io/ios/app/timer-555-calculator-pro/id833443125.md
- Rating breakdown: 5★ 2 · 4★ 1 · 3★ 0 · 2★ 0 · 1★ 0

## Most critical reviews (3 lowest-rated)

### 5/5 — Nice App

*2016-06-05*

Overall a nice app to have.

### 5/5 — Excellent Tool

*2015-09-26*

This is an excellent tool for calculating the best values for a 555 circuit.

### 5/5 — Great app!!

*2014-04-02*

I made an astable NE555 timer/square wave generator according to app instructions (using 2% components). The result was spot on. Nice.

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-04.*