I train groups of 8 senior clients all with individual workouts. Is there software for iPad, iphone to manage these sessions?

Looking for software for iPad or iPhone to manage group training classes of 8 people, all with individual workouts. I am doing fine with paper at the sessions, but bogged down with over 9 hours of paperwork on the weekend transferring workouts and writing new weekly workouts on my computer. Would need to keep track of individual seat settings, weights, and reps, and be able to enter any changes at the session.
Also, add custom exercises. I don't need pictures or any nutrition info.