We've been a little rough on the Presonus StudioLive mixer on the last few episodes. But the truth is, they provide a lot of bang for the buck and will find a home in many a church. And to be fair, Presonus continues to improve and innovate that product line, so we should really given them credit.
QMix is a free iPhone app that gives users the ability to mix Aux sends for monitor mixes. Running in conjunction with the new version of Universal Control (1.5.3 as of this writing), you pair the iPhones with the computer connected to your StudioLive. You can assign permissions to each iPhone and give them the ability to control one mix only. It's really personal mixing on a small scale.
The mix app has some clever features. In landscape mode, the user can easily adjust eight channel levels at a time. The app is very responsive and seemed to work very well.
Turn the phone to portrait mode and it becomes a "more me" control. It's possible to assign multiple channels to "more me' and turn those up as a group. If the musician gets to the top of "more me," and the musician still needs more, the app will turn down other inputs to give the results needed. Very clever.