There are many points to consider before starting into the design and development of an app.
At the core of our team's approach is agile thinking and working, so for us the first step after the idea is to develop what we call a Lean Canvas.
A developer and designer from our team meets with your team and develops this Lean Canvas. Here, the merits of the app idea are identified together with requirements, risks, the competition and, if desired, the corresponding business values.
Depending on the scope of the app, this process can take 1-2 days. Afterwards, however, you receive a condensed, comprehensible and tangible overview of the planned project.
Using the Lean Canvas, our team assesses the expected effort for the design and development of the app. Since our team works according to the Scrum framework in so-called sprints (2-week iterations), however, this effort estimate is only a rough guideline.
The reason for this is that after each sprint the progress is reviewed together with you or your team and the requirements can change accordingly during the development. However, this has the advantage that you usually reach the so-called MVP (Most Valuable Product) status of the app earlier than you originally expected.