I would say that porting Mathematica to the iPad would require them to be able to run the Mathematica engine on iPadOS. And with the strict rules Apple has around arbitrary code execution I would highly doubt that is going to happen.
$ du -h -d3 pkg/Wolfram/
3.1M pkg/Wolfram/WolframScript/bin
3.1M pkg/Wolfram/WolframScript
5.0K pkg/Wolfram/man/man1
5.5K pkg/Wolfram/man
13K pkg/Wolfram/doc/wolframscript
14K pkg/Wolfram/doc
40K pkg/Wolfram/WolframEngine/12.0/Executables
30M pkg/Wolfram/WolframEngine/12.0/AddOns
1.6G pkg/Wolfram/WolframEngine/12.0/SystemFiles
10K pkg/Wolfram/WolframEngine/12.0/Configuration
1.6G pkg/Wolfram/WolframEngine/12.0
1.6G pkg/Wolfram/WolframEngine
1.6G pkg/Wolfram/I just realized that this number is after ZFS compression. Here is the apparent size,
$ du -h -A -d3 pkg/Wolfram/
5.0M pkg/Wolfram/WolframScript/bin
5.0M pkg/Wolfram/WolframScript
8.5K pkg/Wolfram/man/man1
9.0K pkg/Wolfram/man
16K pkg/Wolfram/doc/wolframscript
16K pkg/Wolfram/doc
30K pkg/Wolfram/WolframEngine/12.0/Executables
46M pkg/Wolfram/WolframEngine/12.0/AddOns
2.9G pkg/Wolfram/WolframEngine/12.0/SystemFiles
2.0K pkg/Wolfram/WolframEngine/12.0/Configuration
3.0G pkg/Wolfram/WolframEngine/12.0
3.0G pkg/Wolfram/WolframEngine
3.0G pkg/Wolfram/
Actually the downloaded file is a little over 1 GB, $ stat -f "%z %N" Downloads/WolframEngine_12.0.0_LINUX.sh
1177035547 Downloads/WolframEngine_12.0.0_LINUX.shSounds like the Facebook app.
I think people are okay with gigabyte apps now.
> Apps should be self-contained in their bundles, and may not read or write data outside the designated container area, nor may they download, install, or execute code which introduces or changes features or functionality of the app, including other apps.
It doesn't rule out something like Pythonista (which is great!) that lets you write/run your own code (which doesn't change the app itself).