Studio One is a very stable and lightweight DAW app I ever use and I really appreciate the team who are working on this great app.
I just has a wish for Presonus if your team can have a "live rig" or "live performance" oriented app based on a robust Studio One engine, which may look similar to Main Stage app.
Since S1-4 already has great features like chord track, powerful sampler, MIDI tools, Flexible FX routing, Virtual instrument combination and many more, I think it can be a good idea for Presonus to have maybe a "companion" or "supplemental" app for live performance.
The differentiation with S1-4 is, It may load S1-4 session and incorporate S1-4 markers, arranger tracks or scratch pad in order to playback sequence. It may also stores lyrics, different song session and sound setup (including instruments and FX), tempo, root chord information, and since S1-4 already has chord track engine, it can process root chord change as well. This also need to incorporate smooth sound set transition ...
It is also good if this app can have tight integration with Faderport and Capture to control and record the live performance session too.
I think many idea can come out more if we are talking to this, but at the end is there anyone here who wishes the similar think like I do? 
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