Expert Flyer is a pay site, though they offer free 5 day trials.
I find it invaluable. Historically it has been a must for any American AAdvantage member since it’s been one of the only sources for real-time availability of American Airlines flight inventory and because it also displays confirmable upgrade availability for American’s flights.
Another key feature of Expert Flyer is the site’s alerts. If the space you want isn’t available, you can tell it to email you when it does become available. It isn’t checking in real-time, but multiple times a day, and with increasing frequency as travel approaches so that I’ve generally found it to approximate real-time pretty well.
When I want an award on a flight I can’t get on, or I want a confirmed upgrade, I set an Expert Flyer alert and I get an email when the space I need opens up (or if I’m debating whether or not to confirm an upgrade, I may set an alert for when space is dwindling).
Expert Flyer has added support for much of the Star Alliance. Want to know when Lufthansa first class awards open up? Set an Expert Flyer alert!
Here’s the expanded list of airlines Expert Flyer supports for award search and award alerts:
Note that their data source for Swiss shows availability offered to Miles & More members, and not to partner airlines. Lufthansa and Singapore availability is partner availability (useful if you’re using miles with United, Aeroplan, Lifemiles, etc — but not as useful if you are using Miles & More or Singapore Airlines Krisflyer miles, respectively).
Also, Expert Flyer only supports some special classes for some airlines (outside Star Alliance). For instance, you can’t do Expert Flyer searches or set alerts for Etihad’s saver award space. They support upgrade searches only.
Here’s the upgrade and award classes Expert Flyer supports for each carrier.
This is going to make finding Star Alliance awards much easier. And for folks already subscribing to Expert Flyer, it’s more functionality without a higher price. For others it may just be enough to tip the value proposition into the win column.