JEXER is a fitness facility owned by JR East Group that offers various formats such as comprehensive fitness clubs, women-only gyms and studios, and gym specialty stores. The JEXER official app is an Android-based free app that offers features such as a digital membership card, online reservations, notifications of events and promotions, and access to a variety of workout videos. The app also includes coupons and facility information. To prevent coupon misuse, the app may ask for permission to access storage, which will only save the necessary minimum information. The app recommends using Android 9.0 or newer for optimal performance and may ask for permission to access location information for finding nearby shops or information distribution purposes. The copyright of the content in the app belongs to JR East Sports Co., Ltd and prohibits any unauthorized reproduction, quotation, transfer, distribution, modification, addition, or other acts for any purpose.