A new model powering ChatGPT just led OpenAI to its biggest revenue spike yet. 

Last week, OpenAI debuted its newest large language model, GPT-4o. The new model brought a number of improvements, including faster performance, multimodal capabilities across text, voice, and vision, a new voice mode, the ability to upload screenshots and documents for insights, and more.

Also: I put GPT-4o through my coding tests and it aced them - except for one weird result

GPT-4o is a significant improvement over its predecessor, and arguably the biggest leap for OpenAI yet.

Surprisingly, the company made the model available to all users, including those who don't pay. There's a catch, though: GPT-4o isn't available for free on mobile. That's right; mobile users have to upgrade to ChatGPT Plus to take GPT-4o for a test drive.

According to numbers from AppFigures, this approach worked for OpenAI.

On the day of GPT-4o's release, ChatGPT's mobile revenue rose 22%, the most revenue for the app ever in a single day. That was only the start.

Also: The best AI chatbots: ChatGPT and alternatives

By Tuesday, AppFigures said, the daily revenue for the app was twice the average day in May -- from around$491,000 per day to almost$900,000 per day. (These revenue numbers account for OpenAI first paying Google and Apple for using their app stores.)

The week after the newest language model rolled out, OpenAI saw a total of$4.2 million in app revenue, most of that from Apple's App Store.

What's driving people to pay for GPT-4o when it's available for free? 

Voice input is likely one of the biggest factors, as OpenAI has limited that feature to ChatGPT for Android and iOS. The desktop version only lets you communicate with the AI tool through text, meaning you miss out on the key new integration. 

Accessing chat history offline is another key advantage, as is the faster response time and better integration for the mobile version.

Also: How to use ChatGPT (and how to access GPT-4o)

It's entirely possible, as AppFigures notes, that OpenAI makes more money from its website than its app, which is why it's driving users there instead.

Regardless, the past week shows that not only are consumers extremely interested in the latest developments in AI, but they're also willing to pay to be among the first to get access to the latest from OpenAI.

Artificial Intelligence

Transparency is sorely lacking amid growing AI interest

What is a Chief AI Officer, and how do you become one?

How Adobe manages AI ethics concerns while fostering creativity

6 ways OpenAI just supercharged ChatGPT for free users

• Transparency is sorely lacking amid growing AI interest
• What is a Chief AI Officer, and how do you become one?
• How Adobe manages AI ethics concerns while fostering creativity
• 6 ways OpenAI just supercharged ChatGPT for free users