# Knowe Astro：Birth Chart vs Synastry

The clearest difference is in-app purchases: Synastry at none against Knowe Astro：Birth Chart's 4. Knowe Astro：Birth Chart's advantage is ads (none vs shown). On price, update cadence, device support and iOS requirement there is nothing between them.

Both are free to download. Knowe Astro：Birth Chart sells 4 in-app purchases, starting at $4.99 per month. Synastry asks for nothing beyond the download.

Knowe Astro：Birth Chart ships an update every 4 days, Synastry every 6 days. The most recent releases landed on September 29, 2026 and October 13, 2026 respectively.

## The numbers

| Metric | Knowe Astro：Birth Chart | Synastry |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/knowe-astrobirth-chart/id6752608152/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | Yes | **No** |
| Ads | **No** | Yes |
| Update frequency | **Every 4 days** | Every 6 days |
| Monetization | Freemium | — |
| Size | 22 MB | 15 MB |
| Requires iOS | **18.0** | 18.6 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [占辉 百](https://appshunter.io/developer/1081455103) | [Tryfon Stergiou](https://appshunter.io/developer/1841345608) |

## What reviewers say

### Knowe Astro：Birth Chart

[App page](https://appshunter.io/ios/app/knowe-astrobirth-chart/id6752608152)

This app generates detailed natal charts, synastry comparisons, and transit readings. It offers AI-powered interpretations and includes a built-in astrology library for in-depth study. Ideal for both beginners and experienced astrologers seeking a clear workspace.

**Highlights:** Accurate natal and birth charts, Synastry and compatibility analysis, Transit tracking and timing, AI chart interpretation, In-app astrology library, Detailed placement study

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

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Pro Membership | $4.99 | per month |
| Monthly Ultra Membership | $6.99 | per month |
| Yearly Pro Membership | $19.99 | per year |
| Yearly Ultra Membership | $29.99 | per year |


### Synastry

[App page](https://appshunter.io/ios/app/synastry-daily-transits/id6752854422)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Knowe Astro：Birth Chart free?

Knowe Astro：Birth Chart is free to download, with in-app purchases available.

### Is Synastry free?

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

### Do Knowe Astro：Birth Chart or Synastry have ads?

Synastry shows ads; Knowe Astro：Birth Chart does not.

### Which is updated more often, Knowe Astro：Birth Chart or Synastry?

Knowe Astro：Birth Chart ships an update every 4 days, and Synastry every 6 days. Most recently, Knowe Astro：Birth Chart was updated on September 29, 2026 and Synastry 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.*