The online travel agency’s app, called Booking.com Tonight, is the latest to tap into the market of procrastinating travelers who begin looking for accommodations only after the plane’s wheels touch down.

Many of Priceline’s direct competitors, including Travelocity and Hotwire, offer same-day hotel bookings online. And perhaps the most comparable service is HotelTonight, an app developed by a venture-backed San Francisco start-up. Expedia also has a service called Last-Minute Deals that taps user-generated content so that customers can share deals they’ve found with each other, not using any identifying information.

From what I can tell, however, Priceline’s app is a replica of its online site, offering the same selection of hotel rooms at the same price — where’s the Negotiator now?

Still, the app could be helpful in a pinch, because it has a large inventory of rooms, covering 165 countries. The app also lets you search for rooms based on your location and other filters, such as price, star rating or most popular.

In comparison, the HotelTonight app offers a more boutique experience. It features inventory in only a couple dozen U.S. cities and doesn’t have a huge selection of rooms. In a review, my colleague Katherine Boehret found deals at significant cost savings, including a luxury stay at Langham in Boston’s financial district for $199 rather than $275.

One downside of HotelTonight is that you can’t search for nearby rooms until the afternoon, but if you’ve waited until the day of your stay, then I suppose you can wait a little longer.

Earlier today, Priceline’s stock hit a new 52-week high of $775 a share before pulling back to $753.41. Over the past few years, the stock has soared based on strong international growth.

After promises to get it out midyear, Flipboard is finally releasing its much-anticipated mobile app for the Apple iPhone.

The popular social reader is perhaps the most high-profile available on the iPad, in an ever-crowded field that includes such offerings as Yahoo’s recently launched Livestand; another one code-named Propeller, still upcoming from Google; AOL’s Editions; as well as existing news readers like CNN-owned Zite and Pulse. (Katie Boehret takes a look at the new Flipboard app along with some of those competitors in The Digital Solution this week.)

The Palo Alto, Calif.-based Flipboard, which has raised a pile of money from prominent funders at a big valuation, has been beefing up its advertising business, and a move into mobile was critical.

The new iPhone app, said Flipboard CEO Mike McCue, was built from the ground up, and is different than the iPad version.

For example — don’t get all excited — it flips up rather than side to side. Wheeeeee!

It also introduces “Cover Stories,” which gives you a curated-for-you look at news and social updates.

In related news, after being banned, Flipboard announced earlier this week that its iPad app was now available in China.

Oh, why hear all about it from me? Here’s McCue in a video interview, at the end of which he also dismisses my offer for him to be CEO of Yahoo (apparently, life is too short!):