# Timer 555 Calculator Pro vs ContiConnect Installer

The clearest difference is price: ContiConnect Installer at Free against Timer 555 Calculator Pro's $0.99. ContiConnect Installer also leads on rating (5.0 vs 4.7). Timer 555 Calculator Pro's advantage is ratings volume (3 vs 1). On update cadence, ads, in-app purchases and device support there is nothing between them.

ContiConnect Installer is free to download; Timer 555 Calculator Pro costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ContiConnect Installer holds the better App Store score, 5.0 against 4.7. Both are backed by a comparable volume of ratings — 3 and 1 respectively.

Timer 555 Calculator Pro ships an update every 3 months, ContiConnect Installer every 5 months. The most recent releases landed on June 4, 2026 and June 6, 2026 respectively.

## The numbers

| Metric | Timer 555 Calculator Pro | ContiConnect Installer |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | [4.7 (3 ratings)](https://appshunter.io/ios/app/timer-555-calculator-pro/id833443125/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/conticonnect-installer/id1637378742/reviews)** |
| Number of ratings | **3** | 1 |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 3 months** | Every 5 months |
| Monetization | Paid | **Free** |
| Size | 3 MB | 38 MB |
| Requires iOS | 13.2 | **13.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [Siu Yuen Ho](https://appshunter.io/developer/814088527) | [QUESTAR AUTO TECHNOLOGIES LTD](https://appshunter.io/developer/916723518) |

## What reviewers say

### Timer 555 Calculator Pro

[App page](https://appshunter.io/ios/app/timer-555-calculator-pro/id833443125)

Calculate parameters for monostable and astable circuits. Find component combinations for desired pulse width or frequency. Share circuit files via iCloud Drive or AirDrop.

**Highlights:** Calculate monostable pulse width, Calculate astable frequency, Find component combinations, Adjust component tolerance, Unlimited combinations (Pro), Share circuit files

**In-app purchases:** none


### ContiConnect Installer

[App page](https://appshunter.io/ios/app/conticonnect-installer/id1637378742)

This app facilitates the activation, checking, and testing of connected vehicle units. It allows for system updates and provides a way to verify installation and reception quality.

**Highlights:** Activate units by scanning serial numbers, Read sensor data, Verify unit connections, Perform test drives for reception quality, Update system configurations

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Timer 555 Calculator Pro free?

Timer 555 Calculator Pro costs $0.99, with no in-app purchases.

### Is ContiConnect Installer free?

ContiConnect Installer is free to download, with no in-app purchases.

### Which has better reviews, Timer 555 Calculator Pro or ContiConnect Installer?

ContiConnect Installer is rated higher. Timer 555 Calculator Pro averages 4.7 out of 5 from 3 ratings, while ContiConnect Installer averages 5.0 from 1 ratings.

### Do Timer 555 Calculator Pro or ContiConnect Installer have ads?

Neither Timer 555 Calculator Pro nor ContiConnect Installer shows ads.

### Which is updated more often, Timer 555 Calculator Pro or ContiConnect Installer?

Timer 555 Calculator Pro ships an update every 3 months, and ContiConnect Installer every 5 months. Most recently, Timer 555 Calculator Pro was updated on June 4, 2026 and ContiConnect Installer on June 6, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*