This isn't really a question, but something that I found out the hard way. If you try to bring an image into the app and get an error message like this:
Failed to convert @drawable/(file name) into a drawable
you will want to check the filename. Android Studio doesn't seem to like files that have dashes in the filename. Replacing spaces with underscores seems to be fine, and it accepted a file with capital letters in the title, but it did not like dashes at all.