FREEYOURARP
Currently there are only a handful of arpeggiators and they can be a bit 'complicated'. Blue Arp is one of the most well known ones, as well as the one in Logic Pro.
The restrciction is that it is limited to 3 devices (You can move licenses between devices).
I read about this first on MusicRadar. Here is a youtube demo
This is also an announcement on Gig Performers Forum
BTW I used to use Mainstage, but Gig Performer is so much better than Mainstage and well worth the money. It uses less resources, and it also runs on Windows.
Enjoy!
Put your email into a database.. for this app?