KDDI is offering this service with Starlink and will expand Japan’s land coverage to nearly 100%
In brief – why this matters
– KDDI launches Japan’s first direct-to-cell satellite service, enabling SMS, location sharing, and emergency alerts via Starlink, with no app or hardware required — a critical step for disaster resilience and remote connectivity.
– The service expands Japan’s land coverage from 60% to nearly 100%, overcoming the limits of mountainous terrain and islands — delivering connectivity to underserved areas with over 50 supported smartphone models.
– AI integration allows Android users to text Google’s Gemini assistant via satellite.
Japanese operator KDDI Corporation and Okinawa Cellular have launched a service dubbed au Starlink Direct, which claims to be Japan’s first direct-to-cell satellite communication service.
In a release, KDDI noted that its au customers can use their existing smartphones to send and receive messages via Starlink satellites — enabling connectivity even in the most remote parts of Japan.
The service, developed in collaboration with SpaceX, allows direct communication between smartphones and low-Earth orbit satellites, offering a vital link even in mountainous areas, small islands and offshore locations. No app or additional hardware is needed, and the service is free of charge for now to au users, with no sign-up required, the Japanese telco said.
Although KDDI’s mobile network already reaches 99.9% of the Japanese population, the nation’s rugged topography has historically limited land coverage to about 60%. au Starlink Direct is now extending access to the remaining 40%, the carrier said.
The service currently supports over 50 smartphone models, including Android and iPhones with satellite capabilities.
Users can send SMS, RCS or iMessage texts, share their current location, and receive earthquake early warnings, tsunami alerts, and J-Alerts, ensuring interrupted connectivity even during natural disasters.
KDDI also noted that Android users can also message Google’s Gemini AI assistant for help with information and daily tasks — a unique integration of AI into mobile satellite communications.
Commenting on the launch, Gwynne Shotwell, President & COO of SpaceX, said: “I’m thrilled to bring direct-to-cell connectivity to Japan through KDDI — the first in Asia and one of the first worldwide. Starlink and direct-to-cell technology are game changers, offering potentially life-saving capabilities during emergencies.”
KDDI and Google Cloud Japan had recently signed a Memorandum of Understanding (MoU) to explore the future of AI in Japan. The partnership will center around Google’s advanced Gemini generative AI model, with plans to integrate it into KDDI’s domestic infrastructure, such as the Osaka Sakai data center, within fiscal year 2025.
This initiative aligns with Google Cloud’s strategy of localizing AI infrastructure and services to meet regulatory and performance needs specific to Japan. By leveraging KDDI’s telecommunications expertise and Google Cloud’s AI leadership, the companies aim to deliver accessible, high-performance AI capabilities to both enterprises and consumers.
KDDI said that technical testing is set to begin immediately, opening the door for services that combine AI, edge connectivity and satellite communication.
KDDI is also putting the focus on future 6G networks. Last month, Samsung Electronics and KDDI Research, the R&D institute of KDDI, had signed a Memorandum of Understanding (MoU) for joint research into the application of artificial intelligence (AI) in next-generation mobile communication networks.
As 6G standardization gains momentum with AI technology expanding across industries, the two companies said they aim to enhance overall network performance by applying AI to multiple-input multiple-output (MIMO) technologies.
Last year, KDDI Corporation and SoftBank said they have agreed to start discussions to potentially expand the scope of their ongoing collaborative initiative for jointly building 5G networks in Japan through their joint venture 5G JAPAN Corporation.
Specifically, the carriers said they would consider expanding applicable coverage areas from rural areas to areas nationwide and to explore the mutual utilization of 4G base station assets, in addition to the current scope of 5G assets, among other initiatives.
