Note: This would never work out for someone who is not in a workout routine.
Imagine, that you are a person who tries to stay fit and has a regular gym membership. Right now you have to pay extra to get a trainer, and trust me - you should get one. A trainer can really make sure that you are doing your workout right, and getting all that effort in the right places. Now what happens once the trainer package is over? Most of the time, people go on to continue doing that, there is no push to add more weights, or push yourself to continue ahead on the curve.
The other use case is the person who bought one of those all-in-one gym equipments for the home, and do the treadmill and workout from home. There is no way that they can get a trainer onboard.
There is also the fact that the #1 issue that gyms in the country are facing is that, trainers are hard to find, and be trained and retained.
Today if you look at any of the trainer apps out there for mobile or tablets, they all seem to circle around non-machine excercises (pushups, crunches, etc). Ask anyone who works out and they'll tell you that there are far easier ways to no a push up that doesnt count, than to do one in a machine as its equivalent.
The Solution is a Smartphone/Tablet app, which takes a device like the All-in-one gym machine, and asks a few questions like, when was the last time they worked out, the reps that they usually do etc, and ask some goals - there are routine to stay just fit (if you are), there are routines to lose weight, and there are routines to build muscle. It would be brilliant if the app can suggest, depending on what your goal is, how much you should be pushing yourself each day.
There are apps like the 6 Week training app, this would be more or less the same, except that the routines would revolve around the workouts you can do in a machine.
Target: Anyone who is self motivated, and probably has gym equipment at home.