# Ostara Mobile vs ktak

The clearest difference is in-app purchases: Ostara Mobile at none against ktak's 2. Ostara Mobile also leads on device support (3 vs 1). ktak's advantage is update cadence (every 2 days vs every 4 months). On price, ads and iOS requirement there is nothing between them.

Both are free to download. ktak sells 2 in-app purchases, starting at $4.99 per month. Ostara Mobile asks for nothing beyond the download.

Ostara Mobile ships an update every 4 months, ktak every 2 days. The most recent releases landed on September 26, 2026 and October 29, 2026 respectively.

## The numbers

| Metric | Ostara Mobile | ktak |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 2 days** |
| Monetization | — | Free with in-app purchases |
| Size | 62 MB | 58 MB |
| Requires iOS | **15.0** | 16.4 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Ostara Systems Ltd](https://appshunter.io/developer/830539538) | [Raf Tadevosyan](https://appshunter.io/developer/1873905022) |

## What reviewers say

### Ostara Mobile

[App page](https://appshunter.io/ios/app/ostara-mobile/id1545563422)

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

**In-app purchases:** none


### ktak

[App page](https://appshunter.io/ios/app/ktak-simple-invoice-maker/id6814668070)

Create professional invoices quickly with customizable designs and multi-language PDF support. Track outstanding payments, send reminders, and manage client details securely on your device. Offers a free trial for basic invoice creation.

**Highlights:** Create professional invoices in minutes, Supports any currency and country-specific tax, Generate PDFs in 11 languages, Customizable invoice designs with logo, Track outstanding and overdue payments, Send optional overdue reminders, Secure local data storage

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| ktak Monthly | $4.99 | per month |
| ktak Annual | $29.99 | per year |


## Frequently asked questions

### Is Ostara Mobile free?

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

### Is ktak free?

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

### Do Ostara Mobile or ktak have ads?

Neither Ostara Mobile nor ktak shows ads.

### Which is updated more often, Ostara Mobile or ktak?

Ostara Mobile ships an update every 4 months, and ktak every 2 days. Most recently, Ostara Mobile was updated on September 26, 2026 and ktak on October 29, 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.*