Google recently released an app for traveling! I don't love it but it surfaces reservations out of Gmail automatically.
I agree with Lachlan. Google Trips has become indispensable when traveling. It automatically pulls in all of your travel info from Gmail (flights, accommodations, reservations, etc...) and let's you download an easy to read itinerary.
My and @suzywillow used Journy to plan our trip to Lisbon late last year, super useful as someone who hates planning trips and messy logistics. They pair you with a concierge that recommends places to visit, things to do, and restaurants to go to, based on your preferences and budget. They literally plan your day for you.