OpenAI pioneered artificial intelligence and popularized terms like ChatGPT. It continues to redefine our interaction with language models, but other companies, like ours, Yiaho, also contribute to the evolution of GPT language models!
Over the months, the ChatGPT family has expanded with the introduction of versions 3.5, 4, as well as the newcomers GPT-4o and OpenAI o1. Each model has distinct characteristics that meet various needs.
This article aims to explore the specific features of these different versions, but above all, to present you with the free equivalents available on our Yiaho platform.
ChatGPT-3.5: The Foundations
The GPT-3.5 model laid the groundwork for ChatGPT and achieved great success thanks to its ability to generate coherent and relevant text. Its architecture allows it to perform various tasks, such as answering questions, translating languages, and writing creative content.
However, despite these impressive capabilities, GPT-3.5 has certain limitations. It is no longer even available, deemed obsolete.
Indeed, it can sometimes generate incorrect or biased responses, especially when faced with more complex or ambiguous queries. This version remains a good choice for general use, but it can show its weaknesses in more demanding contexts.
At Yiaho, we have chosen to offer an improved version of ChatGPT 3.5, which is both more powerful and completely free. You can find our ChatGPT model accessible online for free here.
GPT-4: A Qualitative Leap
With the introduction of GPT-4, OpenAI made a real leap forward. This model is designed to process more complex information, offering more nuanced results and a better understanding of the subtleties of human language.
In general, GPT-4 is more accurate and less prone to producing absurd responses compared to its predecessor, making it particularly attractive for applications requiring fine and contextual understanding.
Its only drawback is the price! With subscriptions constantly increasing and internal complications at OpenAI regarding the company’s profitability, the cost of AI has become higher and higher. But on our Yiaho platform, as you know, we have made a completely free ChatGPT 4 model available so that everyone can easily use this AI.
The new GPT-4o and o1 with ChatGPT Plus (or free on Yiaho)
The latest GPT innovations focus on even more advanced capabilities with the GPT-4o and o1 models. GPT-4o is presented as the most powerful model to date, capable of processing visual information more efficiently than its predecessor, GPT-4.
On the other hand, the o1 model specializes in reasoning, being able to use external tools and produce structured texts. This model is particularly suitable for complex tasks where in-depth thinking is required. With an expanded context of up to 128,000 tokens, this model allows for richer and more nuanced interactions.
Important: These models are paid, with a ChatGPT Plus subscription. On Yiaho, they are free!
These new models illustrate the improved processing and reasoning capabilities of their systems. As a free alternative, we offer our users a ChatGPT AGI model, which has better reasoning capabilities than the other GPT models we offer.
Here is a comparative table of the different ChatGPT models:
Read about this: How can Yiaho offer you ChatGPT models for free? Explanations
o3, o3-mini, o3-pro, and o4-mini: The new generation of reasoning with ChatGPT Plus (or free on Yiaho)
OpenAI unveiled its most advanced models in 2025: o3, o3-mini, o3-pro, and o4-mini, each designed for specific needs. They are also paid, with a ChatGPT Plus subscription:
- o3: Announced on December 20, 2024, and available since April 16, 2025, it is OpenAI’s most powerful reasoning model, excelling in coding, mathematics, science, and vision. With a 200,000-token context, it integrates tools like web search, Python, and image analysis, while using a “private chain of thought” to solve complex problems. It surpasses o1 with a score of 87.7% on GPQA Diamond and 71.7% on SWE-bench Verified. However, it can be slower due to its in-depth reasoning.
- o3-mini: Launched on January 31, 2025, this model is an economical version optimized for speed and accuracy in technical fields. It is accessible to all ChatGPT users, including free users in “Think” mode, with usage limits.
- o3-pro: Deployed on June 10, 2025, this is the most powerful model in the o series, designed for tasks where reliability takes precedence over speed. It uses tools like Python and web search but can take several minutes to respond due to its high computing power.
- o4-mini: Launched on April 16, 2025, this multimodal model is fast, economical ($1.10 per million input tokens, $4.40 per million output), and performs well in mathematics, coding, and vision. With a 200,000-token context, it replaces o3-mini and offers a cost-effective alternative to o3, while supporting tools like Python and image analysis.
These models introduce “visual reasoning,” integrating images directly into their thought process, and use a security technique called “deliberative alignment” to evaluate queries. However, tests show that o3 and o4-mini can generate more hallucinations than their predecessors, a challenge to monitor.
Which ChatGPT to choose? A range of models… for all needs!
The diversity of models offered by OpenAI meets a multitude of specific needs. Compact versions such as GPT-4o mini and o1-mini offer interesting performance at a reduced cost, while retaining solid capabilities. In addition, some models are optimized for particular tasks, whether it’s coding, visual comprehension, or other business applications.
At Yiaho, we have implemented specific AIs to meet many needs, including an AI for generating code. This versatility allows users to choose the model that best suits their requirements, whether for content generation, customer service, or data analysis.
ChatGPT: What are the next steps?
The future of ChatGPT looks promising, with evolutionary prospects that suggest increased integration of artificial intelligence into our daily lives.
We can expect models that will further improve their reasoning and comprehension capabilities, allowing them to solve more complex problems.
At Yiaho, we are committed to developing specialized AIs in each field to ensure optimal performance for each application. Whether in the medical, legal, or writing sectors, we continue our efforts to perfect each AI available on our platform.
General AI: coming soon?
Although OpenAI o1 and o3 models are not yet considered General AIs (AGI), they represent significant advances towards this goal. These models are designed to reason more complexly, use external tools, and adapt to new tasks, thus showing a learning capacity that could bring AI closer to AGI.
The quest for AGI raises important ethical and societal questions. Security is a major issue: how to ensure that AI does not become a threat to humanity? The European Union has already drafted a text, the AI ACT, to anticipate the problems that these new technologies could cause.
Furthermore, the automation of many tasks could lead to disruptions in the job market, making it essential to anticipate the impacts. Finally, the issue of bias is central; it is crucial to ensure that AI does not reproduce the biases present in the data on which it is trained!
Conclusion: Which GPT to choose?
The choice between GPT-3.5, GPT-4, GPT-4o, o1, and o3 depends on the specific needs of each user.
Each model has its advantages and limitations, and the diversity of GPTs offers solutions adapted to a multitude of applications. Note, however, that the 3.5 model is quite obsolete.
If you want to use the best ChatGPT for all your daily tasks, we recommend trying our free GPT-4, which we make available on our platform! And you, which one do you use? Feel free to leave your opinion in the comments!
