
au Smart Pass is a multi-service subscription platform operated by KDDI, one of Japan’s largest telecom providers, offering services such as music, books, and shopping within a single app. However, its freemium music experience generated little sustained listening. Sessions were short, and the product offered no clear path from casual listening to the standalone music app.
I redesigned the end-to-end playback experience, turning the embedded player into an entry point that encourages deeper listening and guides users toward the full music service.
The new experience increased music play rate from 5% to 34%, raised average listening time from 79 to 121 minutes, and increase conversion to the standalone music app by 7.5%.
User feedback and product observation revealed three issues preventing the embedded player from functioning as an effective engagement and monetization surface.
Promotional banners and playlists pull attention away from playback, making it harder for users to start listening.
Playback only continues within the player page, interrupting listening when users navigate elsewhere in the app.
Users only learn about restrictions through short toast messages that provide little context or guidance.

I aimed to make music easier to start, control, and continue across the app by clarifying playback interactions and supporting continuous listening.
I mapped key user flows to identify where freemium limits occur and planned different forms of interaction to notify users and guide them toward the full music service.

To make playback controls easier to notice and use, the interface separates playback actions from browsing content, moving playlist exploration to a secondary layer.
To support continuous listening, the mini player keeps music playing while users navigate other services and provides quick access back to the full player.
Freemium limits are communicated through graduated notifications—toasts, popups, banners, and ad-music prompts—guiding users to the full music service.



The redesigned playback system introduces a full player and a mini player, making it easier to start listening and keep music playing across the app. Freemium limits now appear at the right moments, helping users understand the value of the full music service.



This project reinforced a simple lesson: monetization only works when the listening experience feels effortless. Making it easier to start and control playback increased engagement first, which then made upgrade prompts more meaningful instead of intrusive.
Because the product serves an older user base, many users increase text size. This revealed that the existing dynamic type implementation frequently broke the layout, so I also took the opportunity to redefine typography scaling rules.