Paris-based Alcatel-Lucent made an announcement at today’s Mobile World Congress cellphone conference in Barcelona, Spain, that could open the door for mobile application developers to build apps that can be instantly available on multiple wireless carriers, rather than having to build a separate app for each operator.

Moreover, Alcatel’s new service — it’s basically a single API that removes the need for  separate APIs to tie an app to SMS, messaging and location services — will work not just with Alcatel-Lucent, but with other wireless operators as well. It’ll also be cheaper for app developers than the existing system. Usually, developers need to pay each wireless operator separately for SMS access, etc. Alcatel’s API-based approach will by design be cheaper.

“Alcatel is bringing in the cheap API services that have popped up for things like location, and bundling them up with carriers’ existing services, and thus lowering costs for developers that are using it,” VentureBeat editor Matt Marshall emailed me after being informed about Alcatel’s pending announcement on Monday. “So why are carriers agreeing to this? Well, Alcatel is saying the carriers will make money by having developers do more business with them (bulk), even if the the average fee goes down, by bringing them back into the fold.”

That seems to be the slogan of nearly every online business, product or service these days: “We’ll make it up on volume.” With investors convinced that the high-margin days of the dot-com and Web 2.0 booms are gone forever, lower prices are the one sure way to draw interest.

The new service is part of Alcatel’s Open API Service announced last year. In an unusually long press releaese Alcatel-Lucent showed to some reporters in advance, the company explained how it expects its initiative to be perceived by its potential customers, the startups and standalone coders who build applications for mobile gadgets:

“The research we’ve done with more than 1,000 developers shows that the bundled approach to aggregation could drive up an API’s value by 200-300 percent. It also shows that developers want to participate in API revenue sharing and have access to service provider analytics.”

Connected planet reporter Rick Karpinski summed up Alcatel’s offer to developers:

“[It’s] an API aggregation and bundling model that packages up collections of APIs and Web services that developers can use to create a new application. One of the problems with the application approaches of OS-centric environments like the Apple iPhone or Google Android is that they route around telco APIs altogether. For instance, rather than using network location they rely on GPS; or rather than relying on telco user info, they tap into social media profiles, and on and on.”

By providing an easy, one-stop hookup to SMS, location and other services, as well as shrink-wrapped analytical data on how their apps are being used, Alcatel expects to sign up developers by the hundreds, if not thousands.

But Alcatel is competing with every pre-existing app store on the planet. Will app developers forego the iTunes App Store, Android Market, Ovi and other app stores in order to hook up directly to wireless operators? Some will, of course. But it seems likely that Alcatel will end up with a certain subset of developers who have serious problems with Apple, Android and Nokia, rather than winning over the majority of those stores’ app makers.

Alacatel, a 19th-century French firm that merged with America’s Lucent in 2006 to form a global telecom giant, has nearly 80,000 employees world wide.