Bugs

Include version (Setting > About > Version)
If not latest, try updating, it may have already been solved
Debug version is equal to the number of commits as seen in the main page
Include steps to reproduce (if not obvious from description)
Include screenshot (if needed)
If it could be device-dependent, try reproducing on another device (if possible), include results and device names, OS, modifications (root, Xposed)
Before reporting a new issue, take a look at the FAQ, the changelog and the already opened issues.
For large logs use http://pastebin.com/ (or similar)
For multipart issues use list like this:
Done
Not done

* [x] Done
* [ ] Not done

Feature requests

Write a detailed issue, explaning what it should do or how. Avoid writing just "like X app does"
Include screenshot (if needed)

File app/src/main/res/values/strings.xml should be copied over to appropriate directories and then translated. Consult Android.com