# Chemical Engineering Formulate vs AI Hub

The clearest difference is review sentiment: AI Hub at 64% against Chemical Engineering Formulate's 0%. AI Hub also leads on price (Free vs $4.99) and update cadence (monthly vs every 8 months). On ads, in-app purchases and device support there is nothing between them.

AI Hub is free to download; Chemical Engineering Formulate costs $4.99 up front. Chemical Engineering Formulate sells 1 one-off in-app purchase and AI Hub sells 8 in-app purchases, starting at $3.99 per 7 days. Whichever you choose, the download price is not the number that matters.

Chemical Engineering Formulate ships an update every 8 months, AI Hub monthly. The most recent releases landed on October 23, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Chemical Engineering Formulate | AI Hub |
| --- | --- | --- |
| Price | $4.99 | **Free** |
| Rating | — | **[4.2 (61 ratings)](https://appshunter.io/ios/app/ai-hub-50-plus-open-source-llm/id6642680351/reviews)** |
| Number of ratings | — | **61** |
| Positive reviews | 0.0% of reviews | **64.1% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 8 months | **Monthly** |
| Monetization | Paid | **Free with in-app purchases** |
| Size | 19 MB | 66 MB |
| Requires iOS | 18.6 | **15.1** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 12+ |
| Developer | [Historycentral.com](https://appshunter.io/developer/1744330560) | [TRIPICAL VIET NAM LIMITED LIABILITY COMPANY](https://appshunter.io/developer/1639507731) |

## What reviewers say

### Chemical Engineering Formulate

[App page](https://appshunter.io/ios/app/chemical-engineering-formulate/id354670363)

This comprehensive reference tool provides over 1,500 formulas, calculators, and conversion charts for chemical engineering professionals and students. It covers a wide range of topics including heat transfer, fluid mechanics, and reaction kinetics, with support for both US and Metric units.

**Highlights:** 1,500+ formulas and calculators, 700+ engineering calculators, US/Metric unit toggle, Dual-unit display, Searchable reference tables, Offline functionality, Save and share calculations

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Chemistry Pro | $3.99 | one-time |


### AI Hub

[App page](https://appshunter.io/ios/app/ai-hub-50-plus-open-source-llm/id6642680351)

Access a wide range of powerful AI models for chat, image, video, and agent generation. This app offers affordable access to multiple leading open-source and commercial LLMs, optimizing performance and providing low-latency responses globally. It includes a free tier and a comprehensive PRO plan for unlimited access.

**Highlights:** Access 50+ open-source and commercial AI models, AI chatbot with vision and document support, AI video generation from images or text, AI agent programming for workload optimization, AI image generation from text prompts, AI Text-To-Speech with .wav export

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

**In-app purchases (8)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly Subscription | $3.99 | per 7 days |
| Monthly Subscription | $6.49 | per month |
| Yearly Subscription | $69.99 | per year |
| Yearly Subscription | $79.99 | per year |
| 25000 Prepaid credits | $12.99 | one-time |
| 3 months PRO \| Non-renewal | $24.99 | one-time |
| Lifetime \| One-time purchase | $149.99 | one-time |
| Lifetime \| PRO plan | $149.99 | one-time |

**What reviewers like**

- 👍 Great value for money
- 👍 Wide variety of AI models
- 👍 Good user interface
- 👍 Easy to use
- 👍 Affordable pricing

**What reviewers complain about**

- 👎 Unclear model capabilities
- 👎 Inconsistent AI responses
- 👎 Input size limitations
- 👎 Missing important models after updates
- 👎 Lifetime purchase value diminished

**Reported bugs**

- Models disappear after updates
- Input size drastically reduced
- Long HTML analyses are blocked
- Claude, GPT 4.1, Gemini 2.5 Pro, etc. not working due to input size limits
- Images not generated or visible

**Requested features**

- Add a dedicated button/toggle for language translation on the start page
- Automatic detection and faster language switching
- Quick access language list
- Ability to download larger PDF files
- Desktop or web-based version


## Frequently asked questions

### Is Chemical Engineering Formulate free?

Chemical Engineering Formulate costs $4.99, and also offers in-app purchases.

### Is AI Hub free?

AI Hub is free to download, with in-app purchases available.

### Do Chemical Engineering Formulate or AI Hub have ads?

Neither Chemical Engineering Formulate nor AI Hub shows ads.

### Which is updated more often, Chemical Engineering Formulate or AI Hub?

Chemical Engineering Formulate ships an update every 8 months, and AI Hub monthly. Most recently, Chemical Engineering Formulate was updated on October 23, 2026 and AI Hub on October 24, 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.*