I travel a fair amount, for work and leisure, and have always found it difficult to consolidate and share all of my travel plans. TripIt was a great tool and an amazing idea, but it's become so awful to use. The web-based experience is horrendous, and the idea of having to subscribe to their pro service just to find out if your flight is on time doesn't sit well with me.
I was introduced to TripCase by our corporate travel agent. They use it as the itinerary sharing platform for all of their customers.
TripCase is nicely designed, is very easy-to-use, and it's free. It's owned by Sabre, so many travel itineraries can be loaded automatically just by entering your booking confirmation number, which is a nice plus.
If you've made a reservation elsewhere, like on a travel provider's web site, you can just forward the email confirmation to firstname.lastname@example.org, and TripCase will automatically parse and figure out the details for you. I've found this to be accurate in almost every instance.
It's really easy to share itineraries with your coworkers or family, and they'll get an update with flight changes.
One of the best benefits is that I've often been notified of a flight delay or gate change in TripCase before any kind of on board or in terminal announcement was made.
Update: You can now even get an Uber ride, right from your itinerary!