# DEF ISL vs 1ISL Challenge

The clearest difference is update cadence: 1ISL Challenge at every 2 days against DEF ISL's every 12 months. DEF ISL's advantage is iOS requirement (13.0 vs 15.1). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

DEF ISL ships an update every 12 months, 1ISL Challenge every 2 days. The most recent releases landed on June 8, 2026 and February 3, 2026 respectively.

## The numbers

| Metric | DEF ISL | 1ISL Challenge |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[1.0 (1 ratings)](https://appshunter.io/ios/app/def-isl/id6447841373/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 12 months | **Every 2 days** |
| Monetization | Free | — |
| Size | 63 MB | 33 MB |
| Requires iOS | **13.0** | 15.1 |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [SRIJAY SOFTWARE SOLUTIONS PRIVATE LIMITED](https://appshunter.io/developer/1656364843) | [1EQ Edutech Private Limited](https://appshunter.io/developer/1711167252) |

## What reviewers say

### DEF ISL

[App page](https://appshunter.io/ios/app/def-isl/id6447841373)

Learn sign language with over 50,000 signs and phrases presented through videos and illustrations. This app is designed for both adults and children, including those who are deaf or hearing impaired, to improve communication and societal connection.

**Highlights:** Extensive sign language library, Over 50,000 signs and phrases, In-built videos, Illustrations, Easy navigation, Accessible for all ages

**Features:** macOS Compatibility

**In-app purchases:** none


### 1ISL Challenge

[App page](https://appshunter.io/ios/app/1isl-challenge/id6742008806)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is DEF ISL free?

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

### Is 1ISL Challenge free?

1ISL Challenge is free to download, with no in-app purchases.

### Do DEF ISL or 1ISL Challenge have ads?

Neither DEF ISL nor 1ISL Challenge shows ads.

### Which is updated more often, DEF ISL or 1ISL Challenge?

DEF ISL ships an update every 12 months, and 1ISL Challenge every 2 days. Most recently, DEF ISL was updated on June 8, 2026 and 1ISL Challenge on February 3, 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.*