SWOT, McKinsey Model, PEST analysis and why does a developer need all this?

Question

Marketing

I've been tormenting my last year at my university and accidentally discovered that marketing is a rather interesting thing. But is it true in practice?
And since I'm a developer, I really want to somehow screw all this dead knowledge to work, because it's a pity to waste so much memory for nothing.
For example, I want to develop a mobile application. How to understand if it is profitable?
On what platform does it make sense to release? How much to spend on advertising?
And what should it be?
How to analyze the target audience, market segment, competitors?
Will SWOT analysis, McKinsey matrix , PEST analysis help me in this situation?
If yes, how to use them in this specificity?
If not, what is used in such cases?
I do not believe that serious companies do not conduct this kind of analysis, I think that there should be more or less scientific methods.
I would be very grateful for the answers, at least for indicating the direction in which to dig;)
PS Literature, articles, anything in Russian / Ukrainian / English / French will do.

Answer 1

All the methods of structuring marketing information you listed (SWOT, McKinsey matrix, PEST) have one problem. Without a thorough knowledge of the topic, you will not be able to build them correctly. But if you delve into the topic, then you will only need these display methods to convey your understanding of the problem to the surrounding dead ends.
In short: SWOT analysis, McKinsey matrix, PEST analysis are great tools for presentations, but not for independent analysis.
For any product, the first task: assessment of the target audience (TA)
You need to start with this.
1. Formulate who the target audience is
2. Estimate its size
3. Find competitors that complement products and leading products for which yours will complement.
4. Estimate the size of the market
5. Estimate elasticity
6. Estimate the cost of one client
7. Calculate the desired profitability of one client.
8. Draw a brief BP and assess whether you fit the expected profitability with the estimated profitability (clause 7)
, etc. etc. In general: - this is only 2 years of MBA training :-)