Ive been working as a junior dev for a few years now and I'm pretty comfortable with the basics of python and some scikit-learn stuff but lately my boss dropped this new project on me involving custom fine-tuning for some internal models and I'm feeling a bit out of my depth. I know the theory mostly but I really need to drill down into the more complex neural network architectures and the math behind backpropagation again because it's been a minute since uni and things have changed so fast with transformers and all that.

The problem is my schedule is absolutely packed right now. I just moved to a new place in south London and my commute on the Southern rail is basically 50 minutes of being squished against a door so there's zero chance of me pulling out a macbook to code in a notebook or watch a long coursera lecture. I've tried using the mobile version of some of the big sites but the UI is usually trash or they just dont work well without a keyboard and a stable connection.

I'm looking for something actually rigorous not just those gamified tap the word apps that feel like duolingo for babies. I need something where I can actually grasp concepts like attention mechanisms or maybe even do some light coding on my phone if thats even a thing that exists yet. My budget is probably around thirty pounds a month if the content is actually good and not just a bunch of recycled blog posts.

Does anyone know any top-rated apps that are actually worth the subscription? I've seen a few ads for things like Brilliant or Enki but I'm worried they stay too surface level for someone who already knows how to write a function and knows what a tensor is. Is there anything out there that treats mobile users like actual engineers? I really need to stay productive during these train rides or I'm never gonna catch up on this project by the end of the month...