I've been testing Mixer out a lot this year (previously known as Beam), and it's really been a great platform for streaming (both games and general webinars, under their "Web Shows" category). This app is a huge step up as it opens up streaming Android games, while also seeing the streamer's face and catching up with chat.
I was very impressed - I was able to do a "Web Show" about my favourite language learning apps and keep it all contained in this app.
The iOS version is more limited, but that's because of how restrictive Apple is. I was able to stream absolutely everything on my unrooted Android device, and beforehand I was going to have to use some complex set-up of a third-party screengrabber to my PC if I wanted to have my webcam show. So much potential for interesting streams here!
When I tested it, a few things needed tweaking, like the option to customize the webcam size, but for a beta it was incredibly solid, and the dev told me that they would have that option in the next update.
Highly recommended!