Back in my corporate days, we used one that was integrated in the MFD on a Citation XLS. We found it cumbersome and distracting. You were "heads down" with a finger on a button clicking "next". Hated it.
Putting it on an iPad seems like a better idea, especially if it's the type where you could click off what was completed-no more "Did we complete the approach checklist?"
In the end, I'm with GeeWizzDriver and T'world. Paper checklist is failsafe. There's a reason every major US airline (and most international carriers) still use paper.