# dob vs Ling

The clearest difference is rating: Ling at 3.0 against dob's 1.0. Ling also leads on in-app purchases (none vs 1) and device support (3 vs 1). dob's advantage is update cadence (every 3 months vs every 6 months). On price, review sentiment, ratings volume and ads there is nothing between them.

dob costs $2.99 and Ling $2.99 up front. dob sells 1 one-off in-app purchase. Ling asks for nothing beyond the download.

Ling holds the better App Store score, 3.0 against 1.0. Both are backed by a comparable volume of ratings — 1 and 1 respectively. Written reviews split almost evenly too, at 0% and 0% positive.

dob ships an update every 3 months, Ling every 6 months. The most recent releases landed on October 17, 2026 and October 21, 2026 respectively.

## The numbers

| Metric | dob | Ling |
| --- | --- | --- |
| Price | $2.99 | $2.99 |
| Rating | [1.0 (1 ratings)](https://appshunter.io/ios/app/dob-visual-perception/id981954512/reviews) | **[3.0 (1 ratings)](https://appshunter.io/ios/app/ling/id1435126731/reviews)** |
| Number of ratings | 1 | 1 |
| Positive reviews | 0.0% of reviews | 0.0% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 3 months** | Every 6 months |
| Monetization | Paid | Paid |
| Size | 78 MB | 106 MB |
| Requires iOS | 12.0 | 12.0 |
| Devices | iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Rene Fehr-Biscioni](https://appshunter.io/developer/969998405) | [Royal Institute for Deaf and Blind Children](https://appshunter.io/developer/307217029) |

## What reviewers say

### dob

[App page](https://appshunter.io/ios/app/dob-visual-perception/id981954512)

This app offers exercises to train essential visual skills like attention, coordination, and memory. It's designed for learners of all ages, including children and individuals undergoing rehabilitation, and can be customized to individual needs.

**Highlights:** Visual Attention training, Ocular motility exercises, Hand and Eye Coordination, Motion Perception, Contrast Sensitivity, Face and facial expression recognition, Color Recognition and differentiation, Figure-Ground Perception

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| All exercises | $11.99 | one-time |


### Ling

[App page](https://appshunter.io/ios/app/ling/id1435126731)

This app allows users to conduct and track hearing tests using the Ling Six Sound Test. It helps verify that hearing devices are functioning correctly by playing specific speech sounds and recording results over time, replacing manual record-keeping.

**Highlights:** Conduct Ling Six Sound Tests, Track test results over time, Verify hearing device function, Record results for multiple users, Use pre-recorded male/female voices, Record custom voice prompts, Self-check hearing devices

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is dob free?

dob costs $2.99, and also offers in-app purchases.

### Is Ling free?

Ling costs $2.99, with no in-app purchases.

### Which has better reviews, dob or Ling?

Ling is rated higher. dob averages 1.0 out of 5 from 1 ratings, while Ling averages 3.0 from 1 ratings.

### Do dob or Ling have ads?

Neither dob nor Ling shows ads.

### Which is updated more often, dob or Ling?

dob ships an update every 3 months, and Ling every 6 months. Most recently, dob was updated on October 17, 2026 and Ling on October 21, 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.*