The App is an application that enables the notification of a start in track and field events using images and sounds, as well as other relevant functions, by installing it on a smartphone specified by KDDI ("Supported Smartphone").

The App has the following functions:

Function that conveys the start signal from the Supported Smartphone according to the start signal timing that the user set themselves on the Supported Smartphone that they installed on the App on ("Self-training Function")

Function that uses multiple Supported Smartphones with the App installed, one of which is used as a starter ("Starter Terminal") and the others used by athletes ("Athletes' Terminals"; referred to as "Connected Terminals" collectively with Starter Terminal), and conveys the start signal to the Athletes' Terminals from the Starter Terminal via Bluetooth connection ("Linkage Function")

Information
・This app only runs on Android devices that support Bluetooth Low Energy ("BLE"; Bluetooth 4.1 or later recommended).
・The version of the Athlete's Terminal must be Android 4.3 or later, less than 8.0.
・The version of the Starter Terminal must be Android 5.0 or later, less than 8.0 that can operate in BLE Peripheral mode.
・Bluetooth communication used with the Connected Terminals has a time lag.
・Use the App with the Connected Terminals within 10 meters apart from each other.