The ImageJ2 API is a total rewrite, with no dependency on ImageJ 1.x. The
ij package and subpackages are not provided; instead, classes of ImageJ fall under the
net.imagej package hierarchy, as well as
org.scijava for the foundational ImgLib2 and SciJava layers, respectively.
Great care was taken to avoid use of AWT in all these foundational layers. That said, there may be uses of other Java APIs not present on Android; for example, SciJava Common uses
javax.xml. I am not certain exactly which packages we use which are unsupported on Android. The best way to find out would be to try it.
Start by taking a look at the ImgLib2 library and its tutorials:
Note that some examples convert ImgLib2 data structures into ImageJ 1.x structures for display purposes; obviously you would not be able to use those functions (all part of the
imglib2-ij component) in your Android app.
Unfortunately, no one is (yet) using ImgLib2 or ImageJ2 on Android in anger. So if you try it, expect numerous obstacles. However, it would be very exciting to get this working, and is certainly something I have wanted to do for several years. If you have the time and energy to explore it, I am happy to help in whatever ways I can. (E.g.: ultimately I would like to have a full Android build on our CI system to ensure that the APIs work on Android.)