A brief is a written explanation outlining the aims and objectives of an app.
This is the template I propose to define your briefing.
Country/s – Language/s:
Tone of the communication ( functional, emotional, gaming …):
Context of usage of the app (utility, local, informative, productivity, immersive):
Concepts and materials to take into account for the idea:
Prioritized feature list:
This brief should be complemented with a design brief.