Absolute worst. I spent about 20 minutes trying to login to my account. Square had setup 2-factor authentication (automatically) since the last time I logged in, which resulted in me not being able to log directly in. After a series of "authentication" codes being texted to me I was able to login... however, even as I was logged in, I still had to play the "authentication" game when trying to setup a new phone number. This did not work. I tried calling support, but their automated system said they were closed (this was at 8:30am) and they gave their hours of 6am to 6pm. I deleted my account and deleted the Square app from my Android... time to look for another cc processor.