# OB vs 4

The clearest difference is price: 4 at $1.99 against OB's $14.99. OB's advantage is chart position (#172 vs unranked) and iOS requirement (15.0 vs 26.2). On ads, in-app purchases and device support there is nothing between them.

OB costs $14.99 and 4 $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

## The numbers

| Metric | OB | 4 |
| --- | --- | --- |
| Price | $14.99 | **$1.99** |
| Rating | **[4.4 (65 ratings)](https://appshunter.io/ios/app/ob-xd-auv3-synth/id1465262829/reviews)** | — |
| Number of ratings | **65** | — |
| Positive reviews | 57.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | — |
| Monetization | Free | — |
| Best chart rank | **#172** | — |
| Size | 25 MB | 11 MB |
| Requires iOS | **15.0** | 26.2 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [DiscoDSP LLC](https://appshunter.io/developer/1465262828) | [eiki yonemoto](https://appshunter.io/developer/1814352569) |

## What reviewers say

### OB

[App page](https://appshunter.io/ios/app/ob-xd-auv3-synth/id1465262829)

**Currently charting:** #172 Top Paid · Music (US App Store)

This app emulates the classic Oberheim OB-X synthesizer, offering its rich sound and behavior with added enhancements. It focuses on sonic quality and includes micro random detuning for authentic analog warmth. External effects are recommended to further shape its versatile soundscapes.

**Highlights:** Oberheim OB-X emulation, Recreates original sound and behavior, Added enhancements to original design, Micro random detuning, Rich and good sound quality

**Features:** macOS Compatibility

**In-app purchases:** none

**What reviewers like**

- 🎶 Incredible sound quality
- ✨ Inspiring creative tool
- 🎹 Faithful emulation of classic synth
- 🎛️ Great for programming
- 🎚️ Useful presets

**What reviewers complain about**

- 🐛 Unusable UI on older devices
- 💻 Poor GUI scaling on iPad Pro
- 🎛️ Controls unresponsive or misaligned
- 📉 Limited functionality without updates
- 🤷‍♂️ No clear upgrade path

**Reported bugs**

- Crashes in Audiobus
- Cannot use in MIDI section of Audiobus
- Preset browser issues (scrolling, cut off banks)
- Automation bug with cutoff freq
- UI issues on iPad Pro (buttons misaligned, text cut off)

**Requested features**

- Add last/high priority for mono patches
- Increase polyphony to 8 voices
- MIDI Learn functionality
- Preset browser improvements (categories, scrolling)
- Adjustable keyboard size


### 4

[App page](https://appshunter.io/ios/app/4-pad-sampler/id6760901053)

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

**In-app purchases:** none


## Frequently asked questions

### Is OB free?

OB costs $14.99, with no in-app purchases.

### Is 4 free?

4 costs $1.99, with no in-app purchases.

### Do OB or 4 have ads?

Neither OB nor 4 shows ads.

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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.*