Chinese AI startup StepFun officially launched its first smartphone built around a native AI agent integrated into the operating system, rather than around apps, on October 13, 2026. The device, named STEPX Neo, is priced at 3,999 yuan (approximately $560-$597). Pre-orders opened the same evening on JD.com, Tmall, and Douyin, with the first sale set for October 16, 2026, at 10:13 AM China Standard Time.
🔑 Key Takeaways
- The STEPX Neo is the first commercially available smartphone with a native AI agent in the OS, named Amoo, replacing the traditional app model
- Launch price: 3,999 yuan (~$560) with 12 months of AI access included (100 billion tokens per month)
- The Step AOS 1.0 OS uses Anthropic’s MCP protocol and a proprietary H2A2A layer to execute tasks without screen simulation
- StepFun is preparing a Hong Kong IPO at a potential $12 billion valuation
- Security and privacy concerns persist under China’s National Intelligence Law and known MCP vulnerabilities
A Smartphone Designed Around an Agent, Not Apps
The STEPX Neo differentiates itself from 2026 phones marketed as “AI phones,” which typically layer LLM capabilities on top of standard Android as privileged apps. StepFun claims to have rebuilt its operating system, Step AOS 1.0, from re-engineered components of Android, Linux, and a real-time operating system. The conversational agent, named Amoo (nicknamed “A-zai”), is not a floating overlay but a first-plane OS process, capable of invoking device functions through native calls that entirely bypass the graphical interface.
StepFun first showcased the agent, OS, and STEPX brand at a Shanghai event on July 13, 2026, without revealing pricing or availability. A fuller public unveiling was planned for the World Artificial Intelligence Conference (WAIC) in Shanghai from July 17-20, 2026. At that conference, at least two other Chinese companies – Nubia (a ZTE brand) with the NaviX Ultra and Honor with the Robot Phone – also presented competing devices, which somewhat undermines StepFun’s “first” claim.
“Rather than relying on screen reading and click simulation, the company bets on direct integration via MCP and the H2A2A protocol.”
STEPX Neo launch analysis, October 2026
The MCP Engine: A Radically Different Technical Architecture
At the technical core of Step AOS 1.0 is an atomic capabilities engine using the MCP (Model Context Protocol), an open standard originally created by Anthropic to connect AI models to external tools. The protocol decomposes each device function into four groups – communication, apps, files, and system tools – and exposes each as a callable endpoint. Agent Amoo can thus directly execute tasks such as sending a message, making a payment via Alipay, booking a ride via Didi, or ordering food via Meituan, without simulating screen clicks.
StepFun has also developed a proprietary agent-to-agent layer called H2A2A (Human-to-Agent-to-Agent), allowing partner apps to expose specialized sub-agents to Amoo. Above this engine, Step AOS integrates a natural user interface accepting voice and visual inputs, six microphones paired with a low-power audio chip running Whisper 1.0 for wake-word detection and dictation, a dual-domain memory system separating the user’s personal data from the agent’s working memory, and a hierarchical decision layer that routes simple requests to an on-device Edge model and complex ones to StepFun’s cloud models.
The phone also features a real-time task navigation panel at the bottom of the main screen and a small matrix MiniLED display on the back, showing the agent’s status (thinking, tool call, result) while processing tasks.
Partnerships and Manufacturing
StepFun has secured partnerships with nearly 100 companies and products, including Alipay, Tencent, Ctrip, Didi, Meituan, WPS, and CapCut. These integrations cover payments, travel bookings, food delivery, content creation, and document management. The phone is manufactured by Huaqin Technology, a major Chinese electronics contract manufacturer.
StepFun: A Chinese “AI Tiger” Eyeing an IPO
StepFun was founded in April 2023 in Shanghai by Jiang Daxin, a former Microsoft vice president. The company, officially Shanghai Jieyue Xingchen Intelligent Technology Co., Ltd, is regarded by investors as one of China’s six “AI tigers.” Its investors include Tencent, Qiming Venture Partners, and Shanghai State-owned Capital Investment, an entity linked to the state. In February 2026, reports surfaced that StepFun was preparing an IPO on the Hong Kong Stock Exchange. The Wall Street Journal reported in June 2026 that the company was gearing up for an IPO at a potential valuation of up to $12 billion. In May 2026, StepFun raised $2.5 billion in a pre-IPO funding round, according to Caixin Global.
The 3,999 yuan price includes twelve months of the STEPX Token plan, offering 100 billion tokens per month. StepFun has not disclosed the cost of AI access beyond the first year.
StepFun’s AI Model Lineup
In terms of AI models, StepFun released Step 3.5 Flash in February 2026, a 196 billion-parameter mixture-of-experts (MoE) model with 11 billion active parameters, under the Apache 2.0 open-source license, featuring a 256,000-token context window. Step 3.7 Flash followed in May 2026 under the same license. On September 18, 2026, StepFun launched Step 5 Preview, its flagship model with 600 billion parameters and 27 billion active parameters, capable of ingesting up to 1 million tokens. On the Artificial Analysis benchmark platform, Step 5 Preview scored 44, matching Kimi K3 but trailing Xiaomi’s MiMo-V2.6-Pro, Alibaba’s Qwen3.8-Max, and Z.AI’s GLM-5.3.
| Model | Parameters | Active | License |
|---|---|---|---|
| Step 3.5 Flash | 196B | 11B | Apache 2.0 |
| Step 3.7 Flash | 196B+ | 11B+ | Apache 2.0 |
| Step 5 Preview | 600B | 27B | Proprietary |
Security, Regulation, and Lingering Concerns
From a regulatory standpoint, StepFun and its subsidiary StepX Terminal are subject to Chinese legislation, including the National Intelligence Law (2017), the Cybersecurity Law (2017), and the Data Security Law (2021). These laws obligate any Chinese organization or citizen to support and cooperate with state intelligence services upon request.
The MCP protocol used by Step AOS has also drawn security warnings in 2026. The NSA’s AI Security Center published a document in May 2026 noting that MCP adoption had outpaced its security model, citing weaknesses in access controls, approval workflows, and token lifecycle management. The Cloud Security Alliance’s AI Safety Initiative identified three vulnerability classes in MCP deployments: tool poisoning, the confused deputy problem, and supply chain compromise. Two critical CVEs were disclosed in 2025 and early 2026, including one rated 9.6 out of 10 enabling remote code execution.
In response, StepFun has implemented controls blocking packages containing .env files or API keys in its community marketplace, but these measures do not cover tool poisoning via hidden instructions in tool descriptions, which is difficult to detect at the protocol level.
StepFun’s president is Yin Qi, former founder and CEO of Megvii, a Chinese facial recognition company added to the U.S. Department of Commerce Entity List in October 2019, barred from U.S. investment by the Treasury Department in December 2021, and added to the Department of Defense’s list of Chinese military companies in January 2024. StepFun has not publicly commented on this matter.
Can the Agent Deliver in the Real World? The ByteDance Precedent
Questions remain about the agent’s reliability in real-world conditions. ByteDance’s experience with its Doubao phone agent illustrates the difficulties: in December, ByteDance’s agent was blocked by several major Chinese apps, preventing it from executing cross-app tasks. StepFun’s approach to app compatibility differs: rather than relying on screen reading and click simulation, the company bets on direct integration via MCP and the H2A2A protocol.
Qualcomm, through China president Meng Pu, expressed reservations, saying it was too early to determine whether software crossovers or traditional hardware upgrades would win in the AI phone market. The gap between the July 2026 preview and the October commercial launch also raises timeline questions: the first event revealed the agent and OS but disclosed neither pricing nor sale dates, suggesting the commercial launch genuinely took place on October 13, 2026.
Conclusion: An Ambitious Bet With Significant Hurdles
The STEPX Neo represents the most complete attempt yet to replace the app paradigm with a native AI agent embedded in the operating system. StepFun’s MCP and H2A2A architecture offers a credible alternative to the screen simulation approach used by other Chinese players like ByteDance. However, significant challenges remain: MCP’s documented security vulnerabilities, China’s National Intelligence Law raising legitimate data privacy concerns, and Yin Qi’s Megvii ties to U.S. blacklists that could complicate any international expansion. The true test will be user reception after the first sale on October 16, 2026, and StepFun’s ability to maintain third-party app engagement against the established Apple and Google ecosystems.
Sources
- Decrypt – Chinese Startup StepFun Launches a Phone Built Around an AI Agent
- Startup Fortune – StepFun Unveils the First Agentic AI Phone
- Caixin Global – StepFun Launches Smartphone to Challenge Tech Giants
- Dapta – AI News: AI Agent Phone
- TechTimes – STEPX Neo Review
- Wikipedia – StepFun
This article is published for informational and educational purposes. It does not constitute investment advice of any kind. Always do your own research (DYOR) before making any decisions.
