The Priceline hotels and cars app in 2011 still touted the Negotiator before the company deemphasized Name Your Own Price bidding and whacked William Shatner. The blue color scheme was half-hearted.

Priceline’s iPhone app in 2013 includes flights, although the pecking order is hotels, cars and then flights. When you tap through for hotels there is a smorgasbord of options, including Express Deals without bidding, Tonight Only deals, and Name Your Own Price bidding.

In 2009, this early version of the TripIt app displayed upcoming trips. The colors and icons were fairly drab, and there wasn’t anything here that was very actionable. TripIt today is all about sharing, but there was nothing social on this screen.

TripIt’s iPhone app in 2013 opts for bolder blues, oranges and greens, and you can add plans right from the app, and share them on social media. And, you can designate the name of your trip, with all of its components fitting neatly underneath.

The Hotels.com home screen in 2011 was fairly utilitarian-looking, and flush with the company’s signature red hues. It was a bit of a yawner.

The Hotels.com iPhone app in 2013 has a bright blue background and iconic, inspirational imagery. The emphasis is on “local deals for tonight,” user-generated content, and mobile exclusives.

HotelTonight’s version 1 iPhone app in 2010 featured relatively large and bold hotel photos, and at this juncture you could only book a room for “Tonight” so that was an emphasis. There was no map visible, although there was a map button, and it was too soon for guest ratings.

HotelTonight’s 2013 iPhone app uses more artsy hotel photos, and the lingo has changed to “impulse deals,” which can be booked for more than one night.

The Orbitz Android app in 2010 was a bit cluttered, with the hotel address included in the initial search results. The options to search for hotels by Best Values and Lowest Price would take a back seat in later versions to an emphasis on proximity and maps.

The Orbitz iPhone app in 2013 is cleaner-looking than in 2010, and the push is for Mobile Steals, Hotel Deals, and nearby hotels available tonight. The color scheme is bolder and less distracting with just one shade of orange.

Room 77’s debut iPhone app in 2011 reflected its initial mission — to provide intelligence on specific hotel rooms, and how they fit in, or didn’t, with your preferences. Room views and hotel floor maps were all part of the mix.

The search results pages in Room77’s iPhone app in 2013 documents the company’s evolution into hotel metasearch, with rooms available through Booking.com, Expedia, Getaroom, Room 77 itself, and others.

The hotel search results screen in this 2012 HotelsCombined app was a fairly busy affair with relatively large hotel photos, the distance to the hotel from the user’s current location, and verbiage such as “Per Night” and “Total.” Look at the difference the following year in the next image.

A few design changes in the hotel search results screen in HotelsCombined’s iPhone app in 2013 provides a much cleaner look, with plenty of gray space that’s easy on the eyes. It’s done with some minor tweaks such as using smaller images, running the hotel name flush left, and not cramming the results on top of each other. Sort, filter and map features anchor the bottom of the screen.

When you think of itinerary management organizer TripIt in 2013 perhaps one of the first things that comes to mind is your next flight or hotel stay popping up on Facebook or sharing your upcoming trip plans through TripIt apps with your LinkedIn connections.

You probably associate TripIt with one of its smartphone or tablet apps, and TripIt.com, the website, that is, may be an after-thought — if you consider it at all.

But, when you circle back to the beginning of time in the world of mobile travel apps to circa 2009, when iPhone apps in travel such as TripIt’s and Kayak’s first started emerging on the scene, social media wasn’t high on the priority list in mobile, and neither was geolocation, maps, or traveler ratings or reviews to the degree they are today.

At Skift we previously took a look at The Evolution of Usability on Top Travel Websites. And now, in a period when companies such as HotelTonight and others are executing “mobile first,” or perhaps mobile-only strategies, it’s an opportune moment to review how the user experience has been transformed in the game-changing yet short history of mobile travel apps, as evidenced by the offerings of some leading companies.

While some of the first travel websites arrived on the scene from 1996 to 1998, it was just around four years ago, in 2009, that mobile sites and mobile apps in travel started making their debuts in earnest.

You can take a glimpse at the evolution of the user experience in travel apps through the “before” and “after” images of mobile apps (above) from companies including TripIt, Hotels.com, HotelTonight, Priceline, Orbitz, Room 77 and HotelsCombined.

View the Transformation of Mobile Apps in Travel and the User Experience from Leading Companies in the Gallery Above.

While the free TripIt iPhone app was merely about organizing your itinerary and viewing all its random parts in one place on your smartphone in 2009, today TripIt has free and paid apps on a variety of smartphone and tablet platforms, and you can share your plans on social media, and add new trips from your smartphone.

And, with TripIt Pro you can also track your miles and points, and even receive notifications of when the airline seat you want becomes available.

The gallery isn’t only about design changes, but how some of the companies’ business strategies evolved.

You’ll see how Room 77 pivoted from room-specific intelligence to hotel metasearch.

And, HotelTonight evolved to let travelers book the next night, too, in its self-described and curated “basic,” “solid,” “charming,” “luxe” and “high-roller” properties while retiring “modern” and “classic” designations.

There are some parallels in the evolution of travel websites and travel apps. In recent years, both have become less cluttered and more visually appealing, and many in both categories have dabbled in social media, maps, and travel inspiration.

There are big differences, though, too. You won’t find Mobile Steals from Orbitz, an Expedia notification that you can check into your hotel in six hours, and such an emphasis on booking now, on demand and tonight, via HotelTonight, Priceline and Uber apps with smartphone in hand as you might on their respective websites.

And, you’ll see how the shape of these travel apps have evolved as the design of the smartphones themselves have changed from upgrade to endless upgrade.

Just four years into the history of mobile smartphone and tablet apps feel like a decade’s worth of innovation and upheaval.

But hold on because the mobile revolution in travel will undoubtedly render today’s travel apps passé in merely a year or two of app updates. Then it will be time for another slideshow of the changes.