I recently jumped through Giles Colborne's book "Simple and usable: web, mobile, and interaction design." Although I found some parts of the book felt a little dated (it was released in 2010), there are some excellent product and user experience bits of advice in there.
I picked up Mr Colborne's book hoping to find some ideas and inspiration for simplifying the user interface and experience of Vumi Go, and I wasn't disappointed. Vumi Go is the web app that lets people set up Vumi conversations. It's a bit of a beast: it gives you access to a lot of the powerful things that Vumi can do with its messaging services, but they're complicatedly intertwined with each other.
We've already made some Trello cards for acting on one of the strategies for simplification: removing. Specifically: tidying up the code and interface by removing broken bits and pieces that seem to have kept hanging on.
Here are my sketchnotes from the book.