@SmartGoat StaSh pip can only install pure python packages, which means no packages containing or depending on c code.
pytorch appears to have such c dependencies.
Take a look at torch's pypi file page. The filename indicates that each distribution of the torch package is for a specific OS and architecture.
StaSh pip can only install source distributions, either as .tar.gz, .zip, ... or source wheels (wheels containing none-any in its name).
The same is true for pillow. However, IIRC, it may already be included in Pythonista by default.

**Edit: ** A quick search showed npdl as a possible pure-python deeplearning package. It installs successfully using StaSh.