I want to tell everybody about my experience concerning it security.
I started to looking into how to check all issues of my projects and app and read one article by chance, part of it below:
Full variant here - https://www.nytimes.com/2015/05/13/business/dealbook/owner-of-anonymous-hackers-for-hire-site-steps-forward.html?searchResultPosition=1
Well, after i hired 2-3 professionals hackers and they helped me to do full audit by reasonble cost.
Good luck!
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