# Voltsec vs Second Phone Number

The clearest difference is in-app purchases: Voltsec at none against Second Phone Number's 8. Voltsec also leads on update cadence (every 2 weeks vs every 2 months) and device support (3 vs 1). On price and ads there is nothing between them.

Both are free to download. Second Phone Number sells 8 in-app purchases, starting at $9.99 per month. Voltsec asks for nothing beyond the download.

Voltsec ships an update every 2 weeks, Second Phone Number every 2 months. The most recent releases landed on October 5, 2026 and October 12, 2026 respectively.

## The numbers

| Metric | Voltsec | Second Phone Number |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 2 weeks** | Every 2 months |
| Size | 64 MB | 5 MB |
| Requires iOS | **12.2** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Retinasoft Security, LLC](https://appshunter.io/developer/1506080230) | [Cricket Live Line](https://appshunter.io/developer/6774190521) |

## What reviewers say

### Voltsec

[App page](https://appshunter.io/ios/app/voltsec/id1506080231)

**Features:** macOS Compatibility

**In-app purchases:** none


### Second Phone Number

[App page](https://appshunter.io/ios/app/second-phone-number-2nd-line/id6780895566)

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

**In-app purchases (8)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium (Monthly) | $9.99 | per month |
| 2nd Number Plus (Monthly) | $19.99 | per month |
| 2nd Number Pro (Monthly) | $29.99 | per month |
| Premium (Yearly) | $59.99 | per year |
| 2nd Number Plus (Yearly) | $119.99 | per year |
| 2nd Number Pro (Yearly) | $179.99 | per year |
| 500 Credits | $4.99 | one-time |
| 2000 Credits | $14.99 | one-time |


## Frequently asked questions

### Is Voltsec free?

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

### Is Second Phone Number free?

Second Phone Number is free to download, with in-app purchases available.

### Do Voltsec or Second Phone Number have ads?

Neither Voltsec nor Second Phone Number shows ads.

### Which is updated more often, Voltsec or Second Phone Number?

Voltsec ships an update every 2 weeks, and Second Phone Number every 2 months. Most recently, Voltsec was updated on October 5, 2026 and Second Phone Number on October 12, 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.*