I know nothing about laws, advertisement, or marketing. I would like to have your opinion about making profit of this work.<p>Should I contact the original app developers and propose a deal ? The app is super secured, and I did not find any security breach, I just reverse-engineered it. So I am not sure it will interest them. The app has over 90 million users, and as far as went my research, it seems the API documentation never appeared online.<p>Should I publish a paid app with additional features not in the original app, or make it free with ads ? Is it legal ? I am in EU.<p>Should I start a blog, explain how I did, and offer to sell the documentation ? Is it legal ?<p>Should I sell it on the blackmarket ?<p>Should I write an article and sell the article to a popular website ? Which one ? Is it legal ?<p>Should I start a blog, stay vague and grow an audience ? Then how to make profit ?<p>Overall, what is legal ? Which is the more profitable ? Is there other ways ?
Whether it's technically legal is probably less relevant than the idea that the owner can sue you anyway.<p>At which point you hire a lawyer to prove you're legal, but still at some expense and risk to you.<p>Or, short of that, they could wait and see if you have some success, then find ways to block you. You can adapt, of course, but so can they.<p>Generally, I'd avoid basing your success on someone else's whims.