COSO killed my phone. For a day. This morning, I was usong the COSO app on my phone, was looking a 6-panel graphic attachment. To a post when suddenly my screen froze, would not accept touch input. The buttons all still worked but not the screen. I couldn't restart/shut down cos even that requires touching buttons on screen. So I had to let the battery run down to 0%, which took all day; that was the only way to restart it. Recharging from 0 was pretty fast, only took about an hour.
@jjGravitas I've been using the chrome version for quite a while, here. Works great. A few extra features are available if I flip the phone into landscape mode as the right-hand column with the menu shows up.