Android/iOS developers, how to prepare materials to pass the design to you?

Question

Design

I recently started working on mobile app design. Faced with the question - how to prepare materials for transfer to developers? If on the web I know what css can be implemented, and what needs to be cut and transferred to png, then questions arise. For example, there are icons - in what format and size(s) should they be sent? Or can the developer be given a link to https://design.google.com/icons/ (or just indicate that standard material icons are used)? The application has few graphics, but it is there - a logo, icons, notifications with counters.
And yes, I'm not banned on Google, there are a lot of articles, but they are either not specific enough (cut the layout and pass it on), or they are overly detailed. I would like a description of the process, sufficient for the developer and optimal in time for me.

Answer 1

Here is a good and complete description of what we need.
https://habrahabr.ru/company/rambler-co/blog/256397/