Agreed, it's a more complex procedure to create an app, but the kudos for achievement is proportionality higher. It could therefore be argued that there is a rough balance in terms of motivation (assuming kudos drives motivation).

The fact that educators are not inherently technically adept is precisely why they need devices that can be reset and redeployed quickly and simply. If you take into account the attention span of young kids you can see why these devices have become so popular so quickly.

The target market in this context is a younger age range than the age at which programming should be introduced to the curriculum (admittedly this a contentious issue).

I'd argue that the use of iPads in this setting only reinforces the importance of learning to program when the opportunity present itself. How many of our peers were put off a possible career in programming as a result of the high barrier to entry presented by the flashing cursor and a lack of comprehension of the relevance of writing code? We need a proportionate representation of all personality types in the programming world to provide the best solutions for the non-programmers (at least until everyone is a programmer). Maybe this early exposure will attract people with insights we currently lack to careers in programming.