BARCELONA, Spain — When it comes to smartphones, consumers have an array of choices from Apple to... well, Android.The impression you get stepping into most phone carriers' showrooms is that the programmers behind Apple's iOS and Google's Android are driving most of the innovation in smartphones. You'll find few phones on display that run other software systems.Research firm Gartner says 94 percent of smartphones sales last year were either iPhones or Android devices. Windows Phone and BlackBerry devices made up another 5 percent combined.But what about the remaining 1 percent? They are the wannabes such as Firefox and Sailfish —and many of them are introducing innovative advancements in features and functions.I had a chance to try out some of these little-known systems at the Mobile World Congress wireless show in Barcelona, Spain, this week. Many of these systems aren't even available in the U.S., where I live. Although I don't see myself replacing my Samsung Android phone even if I could, some of these alternative phones have features I envy.---— Firefox OS, from MozillaFirefox is better known for its Web browser. Now, the people behind it are trying to adapt it to run smartphones targeted at emerging markets.Firefox OS launched last summer with three phones, priced around $50 to $70. They are in available in 15 countries, but not in the U.S.At the Barcelona show, Mozilla unveiled plans to expand to additional markets in Latin America and eastern Europe, while ZTE announced two new models. Chipmaker Spreadtrum Communications Inc. also announced a blueprint for any phone maker to make $25 smartphones.The home screen and icons resemble what's found on iPhones and Android.Where Firefox OS starts to differ is in apps. With iPhones and Android, you go to an app store to get new apps. With Firefox OS, you typically have instant access to all apps, the same way you can visit a website for the first time without installing anything.The catch is you need an Internet connection to use apps that aren't on your phone, but many apps need that access anyway to refresh news, social networks or restaurant guides.Firefox OS also has a universal search for all content on the phone and online.There's another neat feature coming to Firefox OS. Swipe from the left side of the screen to flip through recent apps one by one, just like hitting the back button on a Web browser.---— Sailfish OS, from JollaSailfish is based on the Linux operating system and comes from the Finnish company Jolla (pronounced "yolla"). Former Nokia employees created Jolla after that struggling cellphone maker abandoned an in-house operating system in favor of Microsoft's Windows Phone.There's only one phone out so far, and it's sold only in Europe for 399 euros ($546). But Jolla has ambitions to reach Russia and Asia and to partner with other phone makers.Jolla Ltd. also announced last week that it will release a free app that Android users can install to replace the regular Android interface with Sailfish's.I can see getting the hang of Sailfish over time. It emphasizes gestures over tapping. Access many functions by swiping from an edge on the screen.The home screen has nine large rectangles, similar to an elongated tic-tac-toe board. These are filled with up to nine of your open apps, so you can instantly get to any one.You can tap to open an app, but what's neat is you can reach a task directly by pressing gently on the rectangle and dragging your finger. For the mail app, drag from the left to create a new message, or drag from the right to refresh messages. For the phone app, drag from the left to get the dialer, or drag from the right to get your list of contacts.This saves time once you get used to the gestures.To close an app, you can swipe down from the top edge like a window shade. If you're already on the home screen, swipe down to lock the phone.Swipe from the left or the right edge within an app to get the home screen. Do that from the home screen to change background, ring tones and other settings. Or if you replace your phone's back cover with a promotional cover, you get special content, such as social media feeds on "Angry Birds."Apple introduced similar gesture controls with its iOS 7 update last fall, but Sailfish goes much further.There aren't many apps written for Sailfish yet, but Sailfish phones have a special tool for running most Android apps. You won't get some of the gesture functions, though.---— Ubuntu, from CanonicalLike Sailfish, Ubuntu is based on Linux. Unlike Sailfish, there aren't any Ubuntu phones yet. But the company behind it announced partnerships with two phone makers last week. Phones are due to come out this year, likely to European and Asian markets at first.Ubuntu's home page has a series of so-called scopes, arranged by category. One video scope might consist of icons for movies on your phone. Another might have items in your Netflix queue. You can refine what's presented through a universal search. The idea is to let you access content easily, without having to open an app first.Swipe from the left edge to get a launcher. The top has all your open apps, while your favorite apps are underneath those. There's also a home screen scope to search for installed apps and those in the app store.Swipe from the right edge to get your most recently used app. Swipe further for a carousel of all open apps. Just pick one to go straight to it.These systems all have good innovations to help users, but people will find the phone and app selections quite limiting. Sailfish has potential if it can indeed run well on existing Android phones, while Android apps can run on it. I look forward to trying that out when it's released in the first half of the year.