Tracking the success of mobile apps remains more of an art than a science.
But comparisons and estimates are becoming more plausible thanks to new travel and transportation app indexes from App Annie, a Beijing-based mobile analytics company.
App Annie's statistics for downloads are cited by investment analysts more often than any other market research firm's data, though rival Onavo is favored when it comes to estimates of revenue and in-app purchases.
Helpfully, App Annie's new monthly travel indexes categorize apps by four subcategories: "travel aggregator", "hotel and lodging," "ground transportation", and "airlines".
These subcategories are much more systematically defined -- and thus make for fairer comparisons -- than the hodgepodge "travel and transportation" subcategories used by the Apple App Store and Google Play store.
The app stores tend to lump together the industry's best known travel apps with random travel-themed apps, such as currency convertors and packing list tools, while also separating user review sites like TripAdvisor from booking sites such as Skyscanner.
Overall winners
As a group, the three most downloaded travel apps in June in the US across Apple and Android's platforms were ground transportation tool Uber and the booking apps for Hotels.com and Expedia:
Airlines
The most downloaded airline apps in June in the US across Android and Apple platforms were, in order: Delta, Southwest, United, American, US Airways, JetBlue, Alaska, Allegiant, British Airways, and Lufthansa.
Some context from App Annie:
"Among US carriers, June’s top 7 airlines by downloads exactly mirrored the top 7 airlines by domestic revenue passenger mile."
One question is if Virgin America will be able to break into the top 10 after its recent full redesign of its app.
Note: "most downloaded in June" obviously doesn't mean most-downloaded of all time. United, for instance, claims 13 million downloads since launch.
Another caveat: While App Annie is the favorite source among investment analysts for measuring app downloads, it doesn’t have a great sense of which apps keep users engaged after the first day -- something that's more of relevance to travel companies.
Hotels & lodging
This sub-category includes apps published by hotel and lodging companies, including peer-to-peer lodging services. It does not include aggregators that search across multiple hotel and lodging companies -- though it curiously groups same-day booking apps like HotelTonight and WeHostels as aggregators.
The most downloaded hotels and lodging apps in the US in June were, in order: Airbnb, Marriott, HomeAway, Hilton, IHG, SPG, Choice, Dwellable, Best Western, and RCI (a timeshare platform).
The performance of Dwellable is impressive, given that its relative lack of funding and marketing resources (see Tnooz profile on Dwellable, here).
Travel aggregators
The most downloaded apps of travel aggregators in June in the US were, in order: Hotels.com, Expedia, TripAdvisor, Kayak, Priceline, HotelTonight, Orbitz, Booking.com, Hotwire, and CheapOair.
That's an impressive performance for HotelTonight, which is now beating the booking apps of household brand names Orbitz and Hotwire, though it would also be interesting to see it compared with hotel and lodging apps in the previous index.
Booking.com is a relatively new entry to the US market, and its position may advance in the tables later this year.
App Annie plans to update its travel rankings for each category every month.
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