In pictures: 15 must-have iOS apps you can't get on any other platform

The Best iOS Exclusive Apps I recently bought an iPhone 5S. It was a big move for me, because I'm kind of a BlackBerry loyalist and a long-time Android user. It's been years since I last carried an iPhone. But as a journalist covering mobile devices, it was time to familiarize myself once again with iOS and the iPhone. The first thing I did when I got my iPhone was seek out quality apps I can't get on any other platform. After all, that's the advantage cited most often when people compare iOS to other mobile software. After digging through the App Store and querying followers on social networks, I came up with the following 15 iOS apps, all of which continue to impress me.
Tweetbot (iPhone and iPod touch) It makes sense that the iOS-exclusive app most recommended by my Twitter followers was a Twitter app. There are tons of Twitter apps for iOS and other platforms, but Tweetbot is the cream of the crop thanks to its clean, intuitive interface and plethora of useful features. It supports multiple accounts—a must for me—while its customizable bottom bar lets you choose the options you use most. You can pick the various, link-shortening, image- and video-uploading, and read-it-later services you prefer, too. Tweetbot's custom sounds and smart gestures also help make this mobile Twitter experience truly unique.
LinkedIn CardMunch (iPhone, iPad and iPod touch) CardMunch lets you snap quick images of all the business cards you receive. It then creates contact listings based on the cards, which you can import into your iPhone or iPad contacts. The app comes from LinkedIn and, as such, it also ties relevant LinkedIn profile information to new contacts, where available. You have to wait a little while for new cards to be converted into contacts, but the service works very well, in my experience, and still saves you a bundle of time by not manually entering new contact information.
Mextures (iPhone, iPad and iPod touch) Mextures is just one of many iOS-exclusive photo editing applications that deserve a home on your iDevice. The app lets you apply "textures" to your images and then add "layers" for custom creations. The true value of the app is in fiddling with the textures and layers to find combinations you love, which you can then save as "Formulas" for use on other images. The app makes other users' popular Formulas available as well. Mextures is also a must for avid Instagramers.
MegaReader (iPhone, iPad and iPod touch) MegaReader is one of the most robust and useful eReader apps I've come across. There's certainly no shortage of similar apps for iOS, Android and the other mobile platforms. But MegaReader is different because its interface is completely customizable. It makes finding interesting books from recognizable authors simple; you just navigate the alphabetical catalogue of books, which is composed of more than 1.8 million free options, and download the ones you want. MegaReader offers access to tons of classic novels, but you'll also find new works from indie publishers and authors.
IFTTT (iPhone, iPad and iPod touch) IFTTT stands for "If This, Then That." That's the basic premise behind the app. You choose one smartphone function and set it to trigger another. For example, if you want to post all of your Foursquare checkins to Facebook, you'd create a recipe for "If This (Foursquare) Then That (Facebook)." The app offers a ton of user recipes that you can take advantage of, and the possibilities are endless. (Read more specifics about IFTTT here.)
iA Writer (iPhone, iPad and iPod touch) The iA Writer app is about as simple as a text editor can be. It saves your writings in .txt files with no formatting. It automatically saves and syncs with iCloud and Dropbox. It auto-names files and lets you change them as you wish later on. The iA Writer keyboard has commonly-used punctuation keys on its main screen so you don't need to swap back and forth between keyboard screens, and it also has forward and back buttons for quick navigation. Text-editing apps are available for all mobile platforms, but iA Writer is one of the cleanest, simplest and most functional that I've used.
Cal (iPhone, iPad and iPod touch) The free Cal app for iOS takes your default calendar to the next level by pulling in your existing calendar and contacts information and incorporating it in a more visually appealing package. If you have a friend's image saved in your contacts, it's tied to any upcoming meetings or dates you may have with them. The app enriches each calendar event with maps and social integration, among other things. Its clean, streamlined interface makes navigation impressively simple.
VSCO Cam (iPhone, iPad and iPod touch) If there's one specific area in which iOS apps far outshine other platforms, it's photography, and VSCO Cam is one of the cooler, more unique photography downloads. The free app gives you endless options to tweak and enhance your photos, with editing tools for exposure, temperature, contrast, cropping, rotation and much more. "Packs" of filters are available for free, and you can purchase more. You can import and export full resolution images, and the app makes sharing on social networks simple.
Kickstarter for iPhone (iPhone, iPad and iPod touch) Kickstarter, the "world's largest funding platform for creative projects," has an official mobile app—and it's an iOS exclusive. The app lets you easily find the latest projects, donate funds, watch related videos and get updates on initiatives you support. If you have project listed on Kickstarter, the app lets you track your funding progress, keep in touch with your supports and provide instant updates while on the go.
LoungeBuddy (iPhone, iPad and iPod touch) Frequent air travelers will find a friend in the free LoungeBuddy app that, as its name suggests, helps you locate relevant airport lounges during your travels, along with information on each of them. It's particularly handy for people with airline loyalty memberships during long layovers, as it spotlights offers available specifically to program members. Killing time with a drink in comfy lounges is always preferable to sidling up to overcrowded airport bars with bulky carryon luggage, and LoungeBuddy helps you quickly locate the appropriate lounges for you.
Diptic PDQ (iPhone, iPad and iPod touch) The free, basic version of Diptic is available for Android in addition to iOS, but the newest iteration, Diptic PDQ (Pretty Dang Quick) is only on the App Store. Both apps let you take a number of images and combine them into collages with various border styles and other effects. Diptic PDQ has an improved interface and gives you new control over the creation process, though, with additional functions to quickly swap out or switch image positions, among other things. Diptic PDQ is a must-have app all for all photo aficionados.
Plants v Zombies 2 (iPhone, iPad and iPod touch) I am really not a gamer. Not at all. But I'm hopelessly addicted to Plants vs. Zombies 2. I played and completed the first installment on my Android phone, and until I got my iPhone 5s, I was anxiously awaiting the sequel, which is only available for iOS in the United States. The game is fun, beautifully designed and hilarious. It's free. And it's a great way to kill a few hours on a cross-country flight. But be forewarned: The zombies can, and will, eat your brains
Timehop (iPhone, iPad and iPod touch) The idea behind Timehop is incredibly simple: Go back one, two, three years, etc., and remind users what they were doing on those specific days on social networks. Depending on the services you connect, you see tweets, Facebook posts, Instagram images, Foursquare checkins and more. I was skeptical at first—why would I care? But I admit, the app has really grown on me. Just yesterday Timehop reminded me, via an old tweet and Instagram image, of how depressed I was after the Red Sox collapse of 2011. Now I'm much more appreciative of the team's position this year. (Go Sox!)
Alien Blue (iPhone, iPad and iPod touch) One of the best Reddit clients I've used on any platform, Alien Blue provides all of the features avid Redditors need in a clean, simple and intuitive interface. And it's also free. Other Reddit apps are available for a variety of mobile platforms, but Alien Blue is one of my favorites. A $1.99 "pro" upgrade unlocks advanced features, including comment-link previews and "Retina" thumbnails (for devices with Retina displays), among other things—but the free version is packed with everything you need to embrace Reddit on the go.
The Eck App (iPhone, iPad and iPod touch) Come on, who doesn't want to learn more about—and even make themselves look like—MLB legend, Hall of Famer and skilled baseball commentator Dennis Eckersly? I gotta have it! The Eck App gives you access to an "Eckipedia" of Eckersly terms; a What the Eck section to test your knowledge of Eckisms, and an Eck Yourself feature to superimpose Eck "moss" on people, pets, whatever, in your photos. OK, it might not be a "must have" app for everyone, and some people I showed it to didn't find the software as amusing as I do. But to that I say: Go Eck Yourself.