Useful Apps is a free and easy-to-use program developed by Onkyo Corporation for Android users. It is specifically designed for ONKYO and Pioneer Digital audio players running Android OS. This app allows you to access ONKYO and Pioneer developed apps, as well as music streaming service apps available in your region from GooglePlay. You can select your region from the "Setting" option and tap on the listed icons to be redirected to the app's download page on GooglePlay.

With Useful Apps, you can quickly access different apps without navigating through your device's interface. However, keep in mind that downloading over cellular communications may result in additional data plan fees.

Overall, Useful Apps is a convenient tool for ONKYO and Pioneer users who want to easily access their apps and discover new ones.