I am still monitoring this thread, the subscription is still live.
When I first moved to Android I used the travel world (?) or World mate (?), cant remember which. It was effectively BBtravel for other devices. It worked well, but I've since moved to using Google Inbox. It automatically pulls details and groups them according to date and location, it presents multiple emails in a seperate, I know this isn't the right word but, folder so that you can see the trip at a glance. For example it has pulled a work trip from an email from our corporate TA and added the relevlant details into my calendar and reminders in the inbox. Car hire was pulled from a seperate email and it has prompted me to book accommodation. I think it works really well and as it effectly my email app it means I have access offline after first access. It works for me by YMMV