# SOLID Architecture vs PhlashCards Security Test Prep

The clearest difference is update cadence: SOLID Architecture at every 9 days against PhlashCards Security Test Prep's every 3 months. SOLID Architecture also leads on iOS requirement (13.0 vs 18.6). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. SOLID Architecture sells 3 one-off in-app purchases and PhlashCards Security Test Prep sells 4 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

SOLID Architecture ships an update every 9 days, PhlashCards Security Test Prep every 3 months. The most recent releases landed on September 16, 2026 and September 6, 2026 respectively.

## The numbers

| Metric | SOLID Architecture | PhlashCards Security Test Prep |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Every 9 days** | Every 3 months |
| Size | 94 MB | 64 MB |
| Requires iOS | **13.0** | 18.6 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Airton Siqueira de Freitas](https://appshunter.io/developer/1809776051) | [Hodge Podgin LLC](https://appshunter.io/developer/1873814194) |

## What reviewers say

### SOLID Architecture

[App page](https://appshunter.io/ios/app/solid-architecture/id6755614891)

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| CERTIFICATE OF COMPLETION | $2.99 | one-time |
| Premium access | $4.99 | one-time |
| FULL PASS ALL APPS | $17.99 | one-time |


### PhlashCards Security Test Prep

[App page](https://appshunter.io/ios/app/phlashcards-security-test-prep/id6759810555)

**Features:** macOS Compatibility

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Security+ Premium | $14.99 | one-time |
| Pentest+ Premium | $14.99 | one-time |
| SecAI+ Premium | $19.99 | one-time |
| CISSP Premium | $19.99 | one-time |


## Frequently asked questions

### Is SOLID Architecture free?

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

### Is PhlashCards Security Test Prep free?

PhlashCards Security Test Prep is free to download, with in-app purchases available.

### Do SOLID Architecture or PhlashCards Security Test Prep have ads?

Neither SOLID Architecture nor PhlashCards Security Test Prep shows ads.

### Which is updated more often, SOLID Architecture or PhlashCards Security Test Prep?

SOLID Architecture ships an update every 9 days, and PhlashCards Security Test Prep every 3 months. Most recently, SOLID Architecture was updated on September 16, 2026 and PhlashCards Security Test Prep on September 6, 2026.

---

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