SoftBank Corp. announced on April 17 that it will be the exclusive Japanese carrier for the “Natural AI Phone,” a smartphone developed by San Mateo, California startup Brain Technologies. The device goes on sale April 24 through SoftBank’s nationwide retail network, with global expansion planned for later in 2026, according to Nikkei Asia and a Reuters wire report.
The phone runs Natural OS, a purpose-built AI-native operating system. The distinction from existing AI-assisted smartphones (Siri on iPhone, Gemini on Pixel) is architectural: Natural OS does not surface traditional app interfaces for the user to navigate manually. Instead, the user gives a natural language command, and the OS autonomously operates the underlying apps to complete the task.
How It Works
Compatible apps at launch include Gmail, Google Maps, Google Calendar, and YouTube, according to Reuters. The app roster is planned to expand sequentially after launch.
A user might say “Schedule a meeting with John next Tuesday at the coffee shop near my office and add it to his calendar too.” Natural OS would then orchestrate across Calendar, Maps, and Gmail without the user touching any app. This is the same agent-to-action architecture that powers desktop computer use agents like OpenAI Codex and Claude Cowork, applied at the mobile OS level.
The Backers and the Distribution
Brain Technologies is backed by Laurene Powell Jobs and Scott Cook, the co-founder of Intuit, according to the GlobeNewswire press release. SoftBank Corp. (distinct from SoftBank Group’s Vision Fund) operates one of Japan’s three major mobile carrier networks with over 30 million subscribers.
The exclusive Japan distribution through a tier-1 carrier in a G7 market makes this the first large-scale commercial deployment of an AI-native smartphone OS. Previous attempts at rethinking the smartphone interface around AI (including the Humane AI Pin and Rabbit R1) shipped as standalone devices without carrier distribution. Brain Technologies took the opposite approach: build the OS, put it on a phone, and sell it through the existing carrier infrastructure.
The Mobile Agent Bet
The launch coincides with a week of desktop AI agent releases (OpenAI Codex computer use, Perplexity Personal Computer, Google Gemini for Mac, Claude Cowork GA). Natural OS extends the same pattern to mobile: the primary interface is not apps but an agent layer that operates apps on the user’s behalf.
Whether Natural OS can deliver on that promise with only four compatible apps at launch is the open question. The answer arrives April 24 in SoftBank stores across Japan.