Setting up web payment using paypal

Setting up web payment using paypal

I'm working on a project and they have are planning to add a feature web
payment. I'm glad to say that our client is a technical person and told me
to use the paypal. This is my first time integrating a web payment. I've
read some docs in developers.paypal and i'm planning to use the paypal
express checkout.
Furthermore I'll be developing this using only client side (Angularjs), is
it right decision for me to use paypal express checkout? Will I encounter
some security issue here since its client side? The main idea is upon
successful payment I have to sync an http request that will trigger that
the user has paid.
Sample idea
.success(function(){
$http.post(...)
});