Nina Castellano

Nina Castellano is a digital payments analyst turned writer, based in London. She spent four years at a European fintech startup, where she specialized in cross-border transaction fees, e-wallet ecosystems, and how payment gateways influence top-up costs for gamers and streamers. That behind-the-scenes experience taught her exactly where hidden surcharges hide—and how to avoid them. Now an independent contributor, Nina focuses on making the payment side of top-ups transparent and user-friendly. From comparing PayPal, Apple Pay, and local e-wallet options to breaking down currency conversion markups, she tests every method herself and reports back with clear, actionable findings. Her guiding principle is simple: every pound spent on fees is a pound not spent on the fun.