# Sightlines vs Undersong

The clearest difference is update cadence: Undersong at daily against Sightlines's weekly. Sightlines's advantage is price ($7.99 vs $9.99) and iOS requirement (13.0 vs 17.0). On rating, ratings volume, ads and in-app purchases there is nothing between them.

Sightlines costs $7.99 and Undersong $9.99 up front. Neither carries in-app purchases, so what you see is what you pay.

On the App Store both sit at effectively the same score — 5.0 for Sightlines against 5.0 for Undersong. Both are backed by a comparable volume of ratings — 9 and 11 respectively.

Sightlines ships an update weekly, Undersong daily. The most recent releases landed on October 24, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Sightlines | Undersong |
| --- | --- | --- |
| Price | **$7.99** | $9.99 |
| Rating | [5.0 (9 ratings)](https://appshunter.io/ios/app/sightlines-harmonic-filter/id6801937031/reviews) | [5.0 (11 ratings)](https://appshunter.io/ios/app/undersong/id6802013758/reviews) |
| Number of ratings | 9 | **11** |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Weekly | **Daily** |
| Monetization | Paid | Paid |
| Size | 19 MB | 19 MB |
| Requires iOS | **13.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Aqeel Aadam](https://appshunter.io/developer/1724235864) | [ian johnston](https://appshunter.io/developer/1886071653) |

## What reviewers say

### Sightlines

[App page](https://appshunter.io/ios/app/sightlines-harmonic-filter/id6801937031)

Shape sounds with a playable harmonic filter. Add motion, stereo spread, and unique textures to noise, samples, or synths. Tune it like a resonator or control it with MIDI for endless sonic possibilities.

**Highlights:** Harmonic filter bank, MIDI control, Sample loading, Noise and synth sound sources, Modulation capabilities, Built-in chorus, delay, and reverb

**Features:** Vision Pro support

**In-app purchases:** none


### Undersong

[App page](https://appshunter.io/ios/app/undersong/id6802013758)

This audio effect acts like an instrument, generating synthesized notes in key based on incoming audio. Explore a vast array of sound combinations with various materials, modes, and patterns for unique ambient performances.

**Highlights:** Generates in-key synthesized notes from audio input, 12 material types and 10 performance modes, 10 pattern options for sound shaping, Self-generating ambient pad mode, Gravity feature for melodic anchoring, Customizable scales and root notes, Integrated reverb effect

**In-app purchases:** none


## Frequently asked questions

### Is Sightlines free?

Sightlines costs $7.99, with no in-app purchases.

### Is Undersong free?

Undersong costs $9.99, with no in-app purchases.

### Which has better reviews, Sightlines or Undersong?

Sightlines and Undersong are both rated 5.0 out of 5 on the App Store, from 9 and 11 ratings respectively.

### Do Sightlines or Undersong have ads?

Neither Sightlines nor Undersong shows ads.

### Which is updated more often, Sightlines or Undersong?

Sightlines ships an update weekly, and Undersong daily. Most recently, Sightlines was updated on October 24, 2026 and Undersong on October 25, 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.*