On December 18, 2025, the operative provisions of Japan's Mobile Software Competition Act — formally the Act on Promotion of Competition for Specified Software Used in Smartphones (スマートフォンにおいて利用される特定ソフトウェアに係る競争の促進に関する法律) — came fully into force. The statute, enacted in June 2024 and administered by the Japan Fair Trade Commission (JFTC), is the country's most consequential intervention in digital markets since the 2020 Act on Improving Transparency and Fairness of Digital Platforms. It compels designated providers of smartphone operating systems and app stores — in practice, Apple and Google — to permit third-party app marketplaces, alternative in-app payment systems, sideloading, and rival browser engines on iOS and Android devices sold in Japan.
For a jurisdiction long viewed as cautious on antitrust, this is a meaningful pivot. But the more interesting story is not that Japan has acted; it is how Japan has acted. Compared with the European Union's Digital Markets Act (DMA) or proposed reforms in the United Kingdom and India, the Japanese law is narrower in scope, more transparent in its triggering criteria, and more procedurally disciplined. It offers a useful template for proportionate, evidence-based platform regulation — provided enforcement does not drift toward the heavier-handed posture seen in Brussels.
What the law actually does
The Act applies only to firms the JFTC formally designates as offering "specified software," defined as mobile operating systems, app distribution stores, browsers, and search engines that meet usage thresholds in Japan. Once designated, the provider must comply with a closed list of obligations and prohibitions. Among the most consequential:
- Sideloading and alternative app stores. Designated OS operators must allow users to install apps and third-party stores outside the first-party marketplace.
- Alternative payments. Developers may offer in-app purchases through their own payment systems, free of forced platform commissions on those flows.
- Browser engine choice. The law ends Apple's long-standing requirement that all iOS browsers use WebKit, opening the door to Chromium, Gecko, and other engines.
- Self-preferencing limits. Designated firms may not unfairly favor their own services in search results or default settings, and must offer choice screens for browsers and search.
- Data portability and interoperability. Developers gain rights to access certain device capabilities and to port operational data.
Violations can be penalized with surcharges of up to 20% of relevant Japanese revenue, with cease-and-desist orders enforceable by the JFTC. Critically, obligations attach only after a formal designation decision, which is subject to administrative review.
Why the Japanese model is more disciplined than the DMA
The contrast with the EU's DMA is instructive. The DMA created a long list of obligations applicable to any "gatekeeper" meeting quantitative thresholds, with the European Commission empowered to designate additional "core platform services" through interpretation. The result has been a near-permanent investigation cycle, with non-compliance proceedings opened against Apple, Alphabet, and Meta within months of the law's effective date.
Japan's drafters appear to have learned from that experience. The Mobile Software Competition Act:
- Targets a specific bottleneck — smartphone software — rather than the entire digital economy.
- Uses ex ante rules only for clearly defined conduct, leaving general competition concerns to the existing Antimonopoly Act.
- Requires the JFTC to publish reasoning for designations and to consult with designated firms before issuing remedies.
- Avoids the DMA's most contested provisions, such as obligations to interoperate with messaging services or to share ranking data with rivals.
This is closer to a scalpel than a sledgehammer. It addresses the genuine competition problem — the duopoly choke point at the mobile OS and app-store layer — without attempting to redesign how every large platform monetizes its services.
The pro-innovation case for cautious optimism
Platform openness is not an unalloyed good. Apple has consistently argued that sideloading degrades iOS security, exposing users to malware and scams that the curated App Store screens out. There is empirical truth to this concern: Android's openness has long correlated with a larger malware footprint, and early data from the EU's DMA implementation suggests a non-trivial uptick in fraudulent sideloaded apps. A pro-innovation stance does not mean ignoring these costs.
The Japanese law strikes a more defensible balance than the DMA in two respects. First, it explicitly permits designated firms to maintain "necessary and reasonable" security measures, including notarization and anti-fraud screening, so long as they are not used to unfairly restrict competition. Second, the JFTC has signaled — through its 2023 Market Study Report on mobile ecosystems and subsequent guidance — that it will weigh consumer protection and security tradeoffs in its enforcement decisions, rather than treating openness as an end in itself.
That posture matters. The point of competition policy is to expand consumer welfare and innovation, not to mechanically dismantle integration. If Japanese developers can reach users through alternative channels while iOS retains its baseline security model, the law will have achieved something the DMA has struggled to deliver: openness without chaos.
What to watch in 2026
The next twelve months will test whether the JFTC can hold this line. Apple and Google have already submitted compliance plans, and disputes over what counts as a "necessary" security measure are inevitable. The JFTC will need to:
- Resist the temptation to import DMA-style maximalist interpretations.
- Publish clear, reasoned designation decisions to give markets predictability.
- Coordinate with Japan's planned Digital Agency oversight functions to avoid duplicative rulemaking.
- Monitor whether alternative app stores are actually emerging — or whether commission rates simply shift without consumer benefit.
If Tokyo can demonstrate that smartphone competition can be opened without breaking the things users value about iOS and Android, Japan's law will become the more attractive global template — not Brussels'. For policymakers in Washington, Delhi, and London still drafting their own platform statutes, that is the experiment worth watching.