There is no way to contact the app. I have a vendor that didn't sent my complete order and hasn't refunded my money. Another seller didn't even send my item and is now saying that Ali Express will refund my money but it's already been a month. In between those two orders it's over $200 dollars that I haven't been able to get back. I have been trying to talk to these vendors and they are just ignoring me. I have an online store and I have spent about a $1000 on this last order.