# Timer 555 Calculator vs NB Now

The clearest difference is in-app purchases: NB Now at none against Timer 555 Calculator's 1. Timer 555 Calculator's advantage is iOS requirement (13.2 vs 15.0). On price, ads and device support there is nothing between them.

Both are free to download. Timer 555 Calculator sells 1 one-off in-app purchase. NB Now asks for nothing beyond the download.

## The numbers

| Metric | Timer 555 Calculator | NB Now |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.9 (8 ratings)](https://appshunter.io/ios/app/timer-555-calculator/id834044557/reviews)** | — |
| Number of ratings | **8** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 3 months | — |
| Monetization | Free with in-app purchases | — |
| Size | 3 MB | 126 MB |
| Requires iOS | **13.2** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Siu Yuen Ho](https://appshunter.io/developer/814088527) | [GOGov, Inc.](https://appshunter.io/developer/351223719) |

## What reviewers say

### Timer 555 Calculator

[App page](https://appshunter.io/ios/app/timer-555-calculator/id834044557)

Calculate monostable and astable circuits for electronics projects. Determine pulse width and frequency, find component combinations, and save/upload data. Supports multiple languages.

**Highlights:** Monostable circuit pulse width calculation, Astable circuit frequency calculation, Component combination finder, Save component values to CSV, Upload CSV via AirDrop/iCloud Drive, Multi-language support

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlock Pro feature | $0.99 | one-time |


### NB Now

[App page](https://appshunter.io/ios/app/nb-now/id6808349003)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Timer 555 Calculator free?

Timer 555 Calculator is free to download, with in-app purchases available.

### Is NB Now free?

NB Now is free to download, with no in-app purchases.

### Do Timer 555 Calculator or NB Now have ads?

Neither Timer 555 Calculator nor NB Now shows ads.

---

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