The current version of Live:Air Action has a limit of sixteen (16) for the combined total of Sources, Shots, and Overlays saved in the app. The maximum amount of Sources for the app is ten (10).
If you exceed this limit, Live:Air Action may crash or have unexpected behavior.
Note that the upper limit of sixteen (16) total has been observed on newer iPad Pro models, but older / lower performance devices such as the iPad Air or iPad Air 2 are expected to have a decreased limit and may not be able to reach this total of sixteen (16).
Our developers are examining if this limit can be raised, as well as the constraints present on each recommended model of iPad from this article.