Japan’s mobile market is a lucrative but complex puzzle for global developers. Why do so many well-funded apps fail to connect with local users? The answer lies in a strategy that goes far beyond simple translation.
We spoke with mobile marketing expert Yu Nakamura to unpack what truly works in Japan. In this Q&A, Yu breaks down the critical nuances of localization, the growing power of rewarded ads, and the key differences in Japanese player behavior that every publisher needs to understand.
AppSamurai: Entering Japan’s app market goes far beyond translation, it demands deep localization, from culturally attuned language to seasonal events tied to holidays. From your experience, how are successful publishers tailoring both their localization strategy and UA approach to resonate with Japanese players, and where do international developers most often get it wrong?
Yu Nakamura: Localization for the Japanese market is a very interesting topic. One common mistake I’ve seen is when publishers try to apply the same strategies that worked in other countries directly to Japan, and end up failing. I believe this happens because Japan has a very different culture as an island nation, and also because the game industry here has developed in its own unique way, with long-established companies like Nintendo and Sony shaping the market.
For smartphone games, a few years ago it felt almost necessary to localize everything into a “Japanese style,” including the art. That was because most of the popular apps in Japan at the time were made domestically. But recently, overseas titles have become more widely accepted, so localizing the artwork is not always essential anymore. On the other hand, careful localization of in-game language is still critical. Japanese players generally don’t feel as comfortable with English as with their native language. So even if a game looks fun, if the tutorial starts out in English, many users will quickly churn. Not everyone, of course, but it’s not uncommon for Japanese players to have a kind of resistance to English in games.
As for UA, not that many publishers are doing heavy localization for Japan. One reason is that many newer games are more non-verbal, and their video creatives don’t include much text.
That said, one channel that has been growing strongly is rewarded ads. Japan has several local rewarded networks in addition to the global ones, and from what I know, there are at least four or five major players. Plus, some new networks are entering the market this year, so I expect this channel will keep expanding in the near future.
AppSamurai: Short drama apps in Japan are growing over 30% YoY, fueled by aggressive paid user acquisition, TikTok-style vertical formats, AI-powered content, and influencer-led discovery. From your perspective, what’s driving this surge more: the aggressive UA or the content strategy itself? And are there lessons that mobile games or other apps can learn from these trends to boost engagement and monetization in Japan?
Yu Nakamura: I believe this growth is being driven by both aggressive UA and the content strategy. Japan has a long-standing manga culture. Titles like Dragon Ball and Naruto, and more recently Demon Slayer, have become global hits, while at the same time there are countless IPs that remain popular only within Japan. Manga was originally consumed through magazines and books, but with the rise of smartphones, it became easily accessible through apps. I see short drama apps as an extension of this trend.
Today, anyone can easily shoot, edit, and distribute videos, which has led to an explosion of content. At the same time, I feel that many users who once spent their time on manga apps are now shifting toward short videos, since they are even easier to consume.
When it comes to mobile games, it might be difficult to directly reapply the same UA strategies. However, there is a lot to learn from the creative side. In recent years, UGC (user-generated content) creatives have been on the rise, and many of the point-reward apps that are growing in Japan rely heavily on UGC-style advertising. In game marketing as well, we are seeing more cases where micro-influencers are being used, and it’s no longer unusual for YouTubers to appear in ads.
Since the effectiveness of a video depends greatly on the channel, I believe the key is to test a variety of creative formats and keep optimizing to find the best fit.
AppSamurai: Japanese mobile games show clear patterns: ad-driven genres lean on volume, while IAP-heavy games benefit from loyalty and retention, with paid UA driving early engagement. From your experience, how should developers balance user acquisition, content investment, and retention strategies across different game types to maximize both engagement and monetization in Japan?
Yu Nakamura: To answer this question, I think it’s important to first touch on the characteristics of Japanese users. Generally speaking, Japanese players tend to immerse themselves deeply in games, they don’t quit easily, and they often continue playing patiently even if the gameplay is somewhat repetitive.
So, if you’re not seeing the kind of user behavior you expect in the Japanese market, I believe it usually means you need deeper localization—especially on the language side. Of course, there are exceptions. Sometimes the issue is simply that the game belongs to a genre that isn’t well accepted in Japan. I won’t point to specific genres here, but if you look at the rankings on the Japanese App Store or Google Play and see several other titles in your category, then you’re probably fine. But if there are almost none, then unfortunately localization alone is unlikely to make it successful.
Coming back to the main point—first, on user acquisition. As I mentioned earlier, I think it’s fine to start by using the same video creatives that work globally and run them through the ad networks. There’s no need to make Japan-specific investments right away; that can come later.
Next, when it comes to content investment and retention. High-quality translation is essential, of course. And in Japan, seasonal events are widely appreciated. This practice comes from Japanese social games, which have long used seasonal events to encourage players to spend on “gacha,” offering new characters or outfits tied to those events. It’s a long-standing cultural expectation, so I think reapplying it still makes a lot of sense.
To sum up, my view on priorities would be: Content investment (mainly language localization) < Retention strategies = User acquisition.
