In the Hobonichi Techo App, BGM and sound effects play in various situations, including the following, to make your daily use of the app more enjoyable.
When launching the app
When "Senpai" speaks
When turning pages
When selecting "Today's Cover"
When receiving "Omake"
When playing a slideshow in full screen on the monthly calendar
How to change BGM and sound effect settings
Tap Menu at the bottom right of the app.
Tap Settings & Payment Information.
Tap Techo Settings.
You will find the "BGM" and "Sound Effects" sections. Slide the buttons to switch them ON or OFF.
*BGM and sound effects will not play when your device is in silent mode.