# Timer 555 Calculator vs BC7701_BLE_OTA

The clearest difference is in-app purchases: BC7701_BLE_OTA at none against Timer 555 Calculator's 1. Timer 555 Calculator's advantage is device support. On price and iOS requirement there is nothing between them.

Both are free to download. Timer 555 Calculator sells 1 one-off in-app purchase. BC7701_BLE_OTA asks for nothing beyond the download.

## The numbers

| Metric | Timer 555 Calculator | BC7701_BLE_OTA |
| --- | --- | --- |
| 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 | — |
| Update frequency | Every 3 months | — |
| Monetization | Free with in-app purchases | — |
| Size | 3 MB | 1 MB |
| Requires iOS | 13.2 | **13.0** |
| Devices | **iPhone, iPad, iPod** | — |
| Age rating | 4+ | 4+ |
| Developer | [Siu Yuen Ho](https://appshunter.io/developer/814088527) | [Holtek Semiconductor(China) Inc](https://appshunter.io/developer/1052056181) |

## 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 |


### BC7701_BLE_OTA

[App page](https://appshunter.io/ios/app/bc7701-ble-ota/id1615919013)

**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 BC7701_BLE_OTA free?

BC7701_BLE_OTA is free to download, with no in-app purchases.

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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.*