# STL Viewer vs Call Scheduler

The clearest difference is price: Call Scheduler at Free against STL Viewer's $0.99. Call Scheduler also leads on update cadence (every 8 days vs every 43 months) and iOS requirement (15.6 vs 17.0). STL Viewer's advantage is in-app purchases (none vs 1) and ads (none vs shown). On monetization model and device support there is nothing between them.

Call Scheduler is free to download; STL Viewer costs $0.99 up front. Call Scheduler sells 1 in-app purchase, starting at $9.99 per year. STL Viewer asks for nothing beyond the download.

STL Viewer ships an update every 43 months, Call Scheduler every 8 days. The most recent releases landed on October 19, 2026 and October 13, 2026 respectively.

## The numbers

| Metric | STL Viewer | Call Scheduler |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/call-scheduler/id6756841097/reviews)** |
| Number of ratings | — | **1** |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 43 months | **Every 8 days** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Best chart rank | **#130** | — |
| Size | 4 MB | 50 MB |
| Requires iOS | 17.0 | **15.6** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Felipe Marques de Barros](https://appshunter.io/developer/1459294806) | [Seiya.k](https://appshunter.io/developer/383021944) |

## What reviewers say

### STL Viewer

[App page](https://appshunter.io/ios/app/stl-viewer/id6445801487)

**Currently charting:** #130 Top Paid · Productivity (US App Store)

Visualize e inspecione modelos 3D STL em seu dispositivo. Oferece ferramentas avançadas para medição, análise de malha e geração de relatórios PDF. Ideal para engenharia, impressão 3D e revisão técnica.

**Highlights:** Multitouch rotation, pan, and zoom, Wireframe, X-Ray, and normal orientation modes, Precise point-to-point measurement, Interactive cutting plane, Mesh health diagnostics, Generate PDF technical reports

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

**In-app purchases:** none


### Call Scheduler

[App page](https://appshunter.io/ios/app/call-scheduler/id6756841097)

Never miss an important phone call again. Schedule calls with specific dates and times, and receive timely notifications. Tap the reminder to instantly open your dialer and connect.

**Highlights:** Schedule call reminders, Tap to dial functionality, Select contacts for calls, Edit and manage scheduled calls, Simple call preparation screen, Local data storage

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Yearly Plan | $9.99 | per year |


## Frequently asked questions

### Is STL Viewer free?

STL Viewer costs $0.99, with no in-app purchases.

### Is Call Scheduler free?

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

### Do STL Viewer or Call Scheduler have ads?

Call Scheduler shows ads; STL Viewer does not.

### Which is updated more often, STL Viewer or Call Scheduler?

STL Viewer ships an update every 43 months, and Call Scheduler every 8 days. Most recently, STL Viewer was updated on October 19, 2026 and Call Scheduler on October 13, 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.*