Pronunciation is very, very difficult to learn by yourself. Find a qualified teacher. Learn the sounds of standard French and the corresponding IPA symbols. Learn the common spelling patterns and the corresponding pronunciation. Read simple stories out loud with a teacher until your pronunciation is "good for a student." Then decide whether to continue with a teacher or to study on your own. I tutor French to children after school. Twenty hours of private instruction (grammar, vocabulary, pronunciation, reading, writing, listening, speaking) equal about a school year of 200 hours of group instruction. In general, when working on pronunciation, my students are "good for a student" after five hours of instruction and practice. Good luck to you.

Salut Cherry, well it's always difficult to start learning French by yourself. As for mobile app there is also Memrise, but I also like Duolingo, it has a very good approach for the very beginners. Anyway you should test some of them to see what type helps you the most. When you'll have some basics there's a good website francaisfacile.com You have tons of good exercises and also people who can help. I also advice you to speak with a French teacher or here on Italki with French people, they can correct and you'll start with a good basics. Bon courage = good luck !

Je suis étudant de la langue française

Duolingo, in case you haven't heard of this app. It's not strictly phonetics, but there is plenty of spoken content. I'd also recommend immersing yourself in just hearing the language, films etc.