How to find the API of a site?

Question

Android

Good afternoon!
There is an online store. I want to write an application for it, but I don't know how to implement their interaction.
Whether the site has an API is not known. What means in this case can be built interaction?
Thank you.

Answer 1

I see only 2 ways:
1) conduct a divination session on the insides of sacrificial animals
2) contact the IT department of the store
UPD
To the comment - "Why does an online store need an API
"
I think you will learn something new

Answer 2

3) still the most bloody - parsing html

Answer 3

Whether the site has an API is not known. What means in this case can be built interaction?

via API and build. no api - make it. there are only 162 lines))
or is the store not yours? then I won’t advise anything, it’s a bad thing to parse other people’s stores. Oh no no no