You are listening to some music and would like to see the sheet music for one or more of the instruments.
An app that displays the sheet music you choose in sync with the music.
NPS is important to measure but not easy to implement.
Add one line of code to you website (or a plugin for a CMS like WordPress) and get all the functionality. You can set multiple types of triggers (exit intent, timed, click a certain link etc.) to activate the button. Visitors can also just click the button. Set up is easy and you just have to click a few options to make it work on a domain and/or URL level.