記念日しおり|カップル・推し・夫婦・大切な人と出会って何日? is an entertainment app by NANAKOROBI with 500+ downloads (about 525 estimated). +7 installs in the last 7 days. Install growth, rank history, SDKs and ad networks.
From the store listing: “Share your schedules and create a single bookmark for dates and trips. You can also easily see how many days you've known each other.”