Article continues below advertisementCassey Ho started Popflex in 2016, but she had been working behind the scenes to bring her vision to life way before that. Article continues below advertisement"It all started with a yoga bag I designed in college when I couldn't find a bag that was equally as functional as it was cute. I needed a bag that could fit all my Pilates class essentials: my mat, keys, water bottle, towel, CD's etc. Everything out there was ugly so I had no choice but to buy fabric and make my own.