Hi.
You have to create the mobileprovision file for this device and compile the app with it. Later you upload the file to Diawi and follow the link or the QR code to install it on the iPhone.
I asked my client if his iPhone and iPad are jailbreaked and he says no, so its not necessary.
I really dont know who is the inner behaviour or configuration of this tool, I only know that it works for our purposes.
I hope to bring some light on it.
Regards.