First, I love being able to select my own sequence of poses from 35 pictures.
I like the ability to substitute music from my iPod, and control whether the instructor gives detailed instructions.
But the Edit page is sorely lacking. They make the text so small to fit the entire workout on one page, that you can barely read the poses. You can delete the last pose(s) you added, add new ones, or finish & name your workout.
But what gets frustrating is the way the left and right sequences are handled. If you add Warrior 1,2,&3, it adds it in this order: Warrior 1 r, warrior 1 L, Warrior 2 r, warrior 2 L, and Warrior 3 r, warrior 3 L. It makes no sense to switch legs like that. A better flow is to do all three Warrior poses on a right front leg and then switch to left front leg and do all three Warrior poses. The same thing goes for Down Dog 2&3, pigeon, and a host of other poses.
What the Edit interface needs is a standard list, where you can select individual poses by line buttons on the right to drag & drop an individual pose, and radio buttons on the left to Delete the selected pose(s).
One app that uses this list interface particularly well is Wunderbears Home Routines.
What seems to complicate matters is the Duration appended to the pose name. Honestly, Id like the Option to edit the poses duration for a yin yoga session.
But what might work in lieu of editing the pose duration is the addition of another row of selectable poses that includes a "15" pose icon that leads to the instruction to continue this pose for 15 more seconds. I can add multiple instances of this 15 pose as needed.
To fill the row, there are certainly other poses that would be worth including in addition to the 15 pose: cobbler, dragonfly, moon, and supported bridge are all great for prenatal workouts but appear to be missing.