Mine works. You can customize what apps show up through spotlight search in settings.
I'm more concerned with how it works. For instance - if I search a name - I'd expect all emails from/to that person to show as well as any emails containing that name. It seems as though it only searches body/subject field ? Am I wrong?
Also, not happy that we can't set third parties as our "default mail app" or a "default maps app" etc through settings to make use of the smarter os [spotlight search, 'remind me of this later', suggestion on departure time to reach a scheduled destination, etc].
If you can and I've missed it - please let me know