Hi there,
The framework is very lightweight and bare bone. It is very good if you don't want to a framework that impose its own structure as it will let you build your own.
You are free of using your own libraries on top of it. No router, no selector, no ajax.
I give advices on the site to use other libraries with it for
common tasks. Just so you can write interfaces for them and completely decoupled external libraries from your own.
It is very good to create decoupled components and re-usable code, thanks to dependency injection and all design patterns tools it provides (commands, mediator, etc).
You write vanilla javascript, not framework classes. Kind of good if you want to build your components from scratch.
There's no magic inside, just pure javascript, so it is just completely fine on mobile.
It is good for any size app and it will shine on larger one. It can be a way out of chaotic javascript and avoid spaghetti code but still need the developer skills to get there.
In short, if you care about unit testing, want to reduce dependencies,
coupling in general, and want to create a highly reusable code in vanilla javascript, it will be the one for you.
I'm about to release a lengthy article that demonstrates how to write scalable applications.
I'll post it back here soon, it should help.
Does that help?
Ask me more precise questions if you want, it will be easier for me to answer.
Romu