MVP
A minimum viable product (aka MVP) is the simplest or scaled-back version of your app that's released publicly to gain feedback from your first set of users. It focuses solely on the core features that offer value but is devoid of all the bells and whistles.
It’s similar to a prototype except it’s fully functional with minimal features and released to a private group of beta users or the public. As such, it’s helpful for gaining feedback on your app but with additional insight into usage which can't be observed with just a prototype in a user interview.
A number of well known apps of today actually started out their journeys as an MVP. It was only after hitting the market did they undergo significant changes, made successful pivots, and ended up where they are today.
For example, Airbnb initially offered a platform where you could book an air mattress, but solely to the people visiting San Francisco for a design conference.