# ATSA SIG vs CallApp

The clearest difference is in-app purchases: ATSA SIG at none against CallApp's 13. ATSA SIG also leads on ads (none vs shown) and device support (3 vs 1). On price and update cadence there is nothing between them.

Both are free to download. CallApp sells 8 in-app purchases, starting at $6.99 per month. ATSA SIG asks for nothing beyond the download.

ATSA SIG ships an update every 2 weeks, CallApp fortnightly. The most recent releases landed on October 5, 2026 and October 17, 2026 respectively.

## The numbers

| Metric | ATSA SIG | CallApp |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.6 (791 ratings)](https://appshunter.io/ios/app/callapp/id6739289261/reviews)** |
| Number of ratings | — | **791** |
| Positive reviews | — | 52.6% of reviews |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | **Every 2 weeks** | Fortnightly |
| Monetization | — | Free with in-app purchases |
| Size | 48 MB | 251 MB |
| Requires iOS | **8.0** | 18.2 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [AERO TRANSPORTE S.A.](https://appshunter.io/developer/1462381236) | [CallApp](https://appshunter.io/developer/1784700170) |

## What reviewers say

### ATSA SIG

[App page](https://appshunter.io/ios/app/atsa-sig/id1467157631)

**Features:** macOS Compatibility

**In-app purchases:** none


### CallApp

[App page](https://appshunter.io/ios/app/callapp/id6739289261)

Identify unknown callers and block unwanted calls with an advanced caller ID. Access a global database of billions of numbers to know who is calling before you answer. Protect your privacy and security with this powerful call management tool.

**Highlights:** Advanced caller ID, Identify unknown numbers, Block spam calls, Global number database, Privacy and security focused, Unwanted call protection

**In-app purchases (8)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly | $6.99 | per month |
| Monthly | $9.99 | per month |
| Monthly | $9.99 | per month |
| Yearly | $29.99 | per year |
| Yearly | $29.99 | per year |
| Yearly | $39.99 | per year |
| Yearly | $39.99 | per year |
| Yearly | $59.99 | per year |


## Frequently asked questions

### Is ATSA SIG free?

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

### Is CallApp free?

CallApp is free to download, with in-app purchases available.

### Do ATSA SIG or CallApp have ads?

CallApp shows ads; ATSA SIG does not.

### Which is updated more often, ATSA SIG or CallApp?

ATSA SIG ships an update every 2 weeks, and CallApp fortnightly. Most recently, ATSA SIG was updated on October 5, 2026 and CallApp on October 17, 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.*