Only the current version so far — new entries appear as the app ships updates.
うさpay is a shopping app by 株式会社まちのわ with 1,000+ downloads (about 1.5K estimated). +2 installs in the last 7 days. Install growth, rank history, SDKs and ad networks.
From the store listing: “Usapay is an app that allows you to easily apply for, purchase, and use electronic gift certificates with just your smartphone.”