Dan 
Unfortunately, the Gmail app on Android doesn’t let you permanently set All Inboxes as the default view when you open the app. Instead, the default is always the Primary inbox. If you set the view to see emails in All Inboxes, close the Gmail app at some point, and open it up again, the app will forget your choice and take you to the Primary inbox view instead.
Chrome is my iPhone and PC web browser of choice. For some time, I was looking for a solution to automatically sync bookmarks of Safari and Chrome web-browsers on my iPhone. Unsuccessfully. When using iPhone’s default Safari iOS app, I had had to manually send web pages (I wanted to keep and open later in Chrome) to Chrome bookmarks using the Safari’s share option.