OpenAI DevDay 2025: GPT-5 Pro, Sora 2 & Platform Updates

OpenAI emphasized that ChatGPT is evolving beyond a chatbot into a full-fledged AI platform or “operating system.” ChatGPT now serves 800 million weekly active users (up from 100M in 2023) and supports 4 million developers using its APIs (^[9]) (^[5]). To leverage this scale, OpenAI announced a new Apps SDK (in preview) so developers can build apps that run directly inside ChatGPT (^[9]) (^[5]). For example, at launch, eligible logged-in ChatGPT users outside the EEA, Switzerland, and the UK could invoke apps such as Spotify and Zillow in markets where those partners offered their services—generating music playlists or filtering real-estate listings without leaving ChatGPT (^[4]) (^[5]).

OpenAI said users could invoke an available app by naming it in a message, while ChatGPT could also suggest an app when relevant to the conversation. Developers could build and test apps using the preview Apps SDK, with submissions planned for later in 2025 (^[10]).

This shift is part of a broader vision to embed ChatGPT everywhere. OpenAI executives likened ChatGPT to an AI “operating system” guiding user-device interaction (^[11]). As ChatGPT head Nick Turley noted, the company imagines the chatbot as a central interface – akin to how a smartphone OS works – eventually powering smart glasses or new hardware as well (^[11]). Although OpenAI isn’t killing traditional interfaces, it’s betting that integrating apps and tools into ChatGPT will make it an indispensable productivity and commerce hub (^[11]) (^[9]).

OpenAI unveiled several new models and model updates at DevDay. Chief among them was GPT-5 Pro, described as a more powerful version of GPT-5 optimized for developers (^[1]). GPT-5 Pro offers “extended reasoning” and uses additional compute on complex problems, making it suited for advanced enterprise and research use cases (^[1]). Importantly, OpenAI said GPT-5 Pro is now available via the API (^[1]), giving developers access to its heightened capabilities. This built on OpenAI’s prior API access to o3-pro, a high-compute version of o3 that OpenAI made available in June 2025 (^[12]).

In parallel, OpenAI introduced new real-time voice models. A new miniaturized voice AI, dubbed gpt-realtime-mini, was announced (^[1]). This model enables interactive voice conversations: it can listen and respond in real time, facilitating applications like automated assistants or chatbots that talk. OpenAI described gpt-realtime-mini as a smaller voice model that was 70% less expensive than the large model. (^[13]) These voice models complement OpenAI’s prior models by offering cost-effective, streamlined voice capabilities.

Another headline was Sora 2, OpenAI’s video-and-audio generation model, released on September 30, 2025. OpenAI described it as adding synchronized dialogue and sound effects, and listed Sora 2 in the API among the DevDay product announcements (^[14]; OpenAI DevDay 2025).

To help developers build AI-powered applications faster, OpenAI announced several new developer toolkits. The centerpiece is AgentKit, described as a toolkit that lets developers “design and deploy AI agents in minutes” (^[3]). Agents are autonomous programs that can perform tasks given instructions – e.g. booking travel, analyzing data, etc. AgentKit builds on the Responses API and lets developers visually compose agent workflows with nodes, tools, and guardrails (^[15]). For example, a travel agent that uses knowledge of user’s calendar and preferences, or a sales agent that automatically drafts proposals. AgentKit was expressly highlighted as a way to simplify the creation of AI-driven workflows (^[3]).

OpenAI also introduced ChatKit, a toolkit for integrating ChatGPT’s chat interface into third-party apps (^[3]). With ChatKit, an app developer can embed a ChatGPT-powered chat box or assistant directly inside their app or website, complete with custom prompts or workflows. For instance, a language-learning app could embed ChatGPT for conversational practice, or a productivity app could offer a ChatGPT helper in the corner.

Moreover, an Apps SDK (also called ChatGPT Apps SDK) was rolled out. This SDK allows existing apps like Canva or Spotify to plug into the ChatGPT ecosystem (^[3]). In practice, it means developers of popular services can expose specific functionality (e.g. a Canva graphics generator or a Zillow listings filter) as “apps” that ChatGPT can call. During the demo, OpenAI showed logos of apps like Spotify and Zillow making ChatGPT more than just text; for example, OpenAI’s CEO Sam Altman mentioned generating a music playlist by voice command in ChatGPT. The SDK is in preview for developers, enabling them to build apps that connect to data, trigger actions, and include interactive interfaces (^[9]).

These toolkits round out OpenAI’s platform approach: not only does OpenAI supply raw models and APIs, but it also provides higher-level frameworks (AgentKit, chat and app SDKs) so that developers can integrate AI into products with minimal effort (^[3]) (^[9]).

OpenAI used DevDay to announce a number of high-profile partnerships across industry, reflecting a strategic shift toward enterprise integration (^[16]). Notably, OpenAI partnered with Spotify (for music), Zillow (real estate), and others to “integrate OpenAI’s AI tools across multiple industries” (^[16]). These partnerships mean that the services of those companies will deeply incorporate OpenAI models – for instance, Zillow can use ChatGPT to automatically organize and filter property listings based on chat queries, or Spotify can let users have conversational playlist creation with ChatGPT.

Consumer brands were also featured: Mattel and OpenAI announced a strategic collaboration to explore OpenAI technologies for AI-powered products and experiences. Their announcement did not identify Sora 2 as the product-development tool or describe a sketch-to-video workflow (^[17]).

The most significant infrastructure deal announced was with AMD. OpenAI entered a multi-year chip-supply partnership with AMD to support the company’s massive compute needs (^[8]). Under this agreement, AMD will provide up to 6 gigawatts worth of its high-performance Instinct MI450 AI GPUs starting in late 2026 (^[8]). The deal is reportedly worth tens of billions of dollars in chips, and it even gives OpenAI an option to buy up to 10% of AMD’s stock at a fixed price (^[8]). This AMD partnership helps OpenAI diversify beyond NVIDIA (with whom it already has previous deals) and addresses the “critical bottleneck” of compute capacity mentioned by OpenAI’s leaders (^[18]) (^[8]). AMD’s shares jumped over 23% on the news of the deal (^[8]).

The focus at DevDay was clear: strengthen the “enterprise chassis.” Altman remarked that parts of the industry are “bubbly,” but affirmed that genuine value is being created and that OpenAI is building a top-tier enterprise platform (^[19]).

OpenAI’s DevDay page reported 800M+ weekly ChatGPT users, 4 million developers who have built with OpenAI, and 6 billion tokens per minute on the API platform (^[13]). These figures describe the scale OpenAI reported for its products and developer platform at the event.

To put it in perspective, Altman noted that OpenAI has more users now than many national platforms, and its roadmap is heavily oriented around scaling those users with new features. (For example, the ChatGPT apps and suggestions are designed to increase how much end users do inside ChatGPT.) The media buzz around DevDay emphasized that OpenAI’s platform approach is turning it into a core infrastructure player for the AI age: “ChatGPT Active User Base: 800 million weekly” was a headline on multiple tech sites (^[20]).

DevDay’s program included “A Conversation with Sam and Jony,” focused on the craft and design process of building tools in the age of AI. The published event description did not announce a hardware product or provide product specifications (^[13]).

Nine months on, most of the DevDay 2025 announcements have followed through, though not without course corrections. This section, added July 10, 2026, updates the record.

Sora’s product availability changed materially. OpenAI says the Sora web and app product became unavailable on April 26, 2026. That does not describe the API’s separate status: OpenAI’s support documentation says the Sora API is scheduled to be discontinued on September 24, 2026 (^[21]).

AgentKit’s availability changed. OpenAI’s AgentKit announcement now says it is winding down the Agent Builder and Evals products; they will no longer be available on the OpenAI platform from November 30, 2026. OpenAI recommends the Agents SDK for workflows that should continue as code (^[15]).

The Apps SDK moved from preview to a real submission pipeline. At DevDay, the Apps SDK and ChatGPT Apps were shown as previews with a handful of launch partners (Spotify, Zillow, Canva, and others). On December 17, 2025, OpenAI opened formal app submissions, publishing developer guidelines, open-source example apps, and a UI library, and it launched an in-product app directory reachable from the ChatGPT tools menu or directly at chatgpt.com/apps (^[22]). The first wave of approved third-party apps began rolling out gradually starting in early 2026 (^[22]). As of that announcement, monetization was still limited: developers could link out to their own sites or native apps to complete purchases of physical goods, with in-chat monetization of digital goods described as still being explored (^[22]). This is a more measured rollout than the DevDay demo implied, but it confirms the Apps SDK direction held.

The model line kept advancing past GPT-5 Pro. By mid-2026, OpenAI’s model guidance described GPT-5.6 as its flagship model and included migration guidance from GPT-5.5 and GPT-5.4, superseding GPT-5 Pro as the headline model news from DevDay 2025 (^[23]; Model Release Notes).

DevDay is scheduled to return in 2026. OpenAI’s announcement lists September 29 in San Francisco and invites people to sign up for application-opening notifications (^[24]).

Net assessment: the platform vision described at DevDay 2025—ChatGPT supporting third-party apps and developers building agents—continued to develop, though product details and availability can change. Readers evaluating Apps or agent tooling should consult OpenAI’s current official product documentation before making implementation or migration decisions.

Overall, the announcements on October 6, 2025 signal that OpenAI is aggressively expanding across multiple fronts. The company is injecting AI into more software and services (through ChatGPT Apps and partnerships), advancing core model capabilities (GPT-5 Pro, Sora 2, voice), and empowering developers (AgentKit, SDKs). It’s also cementing enterprise and infrastructure support with partnerships from media to hardware (AMD’s gigawatt deal alone is in the tens of billions (^[8])). These moves show OpenAI is aiming to be both the foundation and the toolkit for a new generation of AI applications.

In short, DevDay 2025 was “bigger than ever,” as OpenAI itself teased beforehand (^[25]): it delivered on that promise by unveiling a broad vision of AI as an integral part of daily software, business processes, and even future devices. The October 6 announcements make clear that OpenAI intends to shape the next wave of AI innovation for developers and consumers alike (^[26]) (^[8]).

Sources: Official content and news reports from OpenAI, Reuters, Axios, the Economic Times, and other tech media (^[25]) (^[27]) (^[4]) (^[11]) (^[7]) (^[1]) (^[3]) (^[9]) (^[5]) (^[8]).