HI There,
I can assist you with "build new system on WP with FB app", I have experience working with "similar Development".
Let's have a quick chat to discuss it further.
Relevant Skills and Experience
I have been in this "FB app Development" field for a long time now, you can further check my sample work at:
https://www.freelancer.com/u/extreamcode.html
Proposed Milestones
$122 USD - project milestone payment