KOIGAKU is a lifestyle app developed by LINKBAL INC., catering to women seeking to enhance their love lives. The app offers a variety of features to assist women in realizing their ideal relationships. It provides daily updates, over 10,000 free love columns, and relationship advice. Targeted towards women in their 20s and 30s, KOIGAKU covers topics such as love, relationships, work, beauty, and more.

KOIGAKU delivers content ranging from in-depth love columns by renowned writers to relationship advice from popular influencers with a significant Twitter following. The app covers various aspects of love, meeting new people, marriage, beauty, makeup, lifestyle, and fortune telling, making it a comprehensive life support platform.