Read the book “Learning C with Pebble” (slow and many things I already know)
Read code of other Pebble apps and use this as inspiration (how to find the good examples)
Build lots of toy projects using the documentation (slow and I’m not sure the documentation is up to date)
You as an experienced developer of Pebble apps, what would you recommend?
Context: I’m an iOS developer since 15 years. This means I can write Objective-C and Swift code without really thinking about it. I also have done some C programming in my studies 20 years ago. In my spare time I used to build iOS (and some Mac) apps. Now I want to build Pebble watch apps.
Start with the C tutorials, all of the articles in the Guides section also give code snippet examples that show off how to use specific components. Docs should be mostly up to date; if you find broken links open an issue on GitHub or post about it hore and it might get fixed. But the SDK hasn’t changed too much (other than adding new platforms and adding a few compile warnings that don’t go away) so the docs should still be accurate for pretty much everything. The one major exception is that server-side timeline pins are no longer supported by the Core Devices Pebble app. They will work if you create them from within PKJS, but they will not work if you push them from a server.
The fastest way? This is usually not the best way to go about learning things.
Given that you have 15-20 years of experience in development, you can probably get away with writing your app in C as you would any program and then treating pebble as a UI for controlling your input and for displaying your output.
The app that is created when you run pebble new-project my-project already has what you need to get started showing things on the screen and handling user input