With over 700,000 apps available in the iOS App Store, it's impossible to keep track of all the new updates coming down the line every week. And sometimes, there just isn't time for a full hands-on of every great app or update. So we're sharing some of the apps that caught our eye this week. As usual, we're not including every single one that made its way through the tubes—just the ones that seemed worth mentioning.

So what are we waiting for? Here are the apps from this week:

If you liked Sparrow because it provided a fresh way to deal with e-mail, a brand new app called Mailbox may catch your eye. The folks behind the to-do app Orchestra were sick of the inefficiencies and bad UIs in current e-mail clients and decided to build a "mobile-first e-mail experience from the ground up—challenging assumptions about how email works and redesigning the inbox for a world on the go."

The idea is to reformat the way users see and interact with e-mail to make it a better—and more mobile—experience. Part of that includes merging the concept of mail with tasks that need to get done (a common use for e-mail among much of the population), but in a way that doesn't overwhelm the user with on-screen options and settings. Messages are displayed in a very chat-like manner, with the app taking advantage of push notifications, offering the ability to snooze e-mails so you can respond later, and requiring minimal taps to trash or archive items.

Unfortunately for those of us on the outside, Mailbox is rolling out its launch by taking first-come, first-serve "reservations" when you download the app. This means that although you might have the app on your iOS device already, there could be hundreds of people in "line" ahead of you before you can use it (as of this writing, the number is over 350,000). In that sense, the launch of Mailbox this week is kind of a tease—we can look at the pretty screenshots but not play until later. That said, the buzz about Mailbox is building, so it seems worth checking out once you make your way to the top of the list.

TED 2.0: free

This one was just released on Friday and it's largely similar to the 1.0 version of the TED app. What makes version 2.0 different is that it apparently has tweaks to make video buffering faster—certainly useful for those of us who watch TED talks via cellular data connections.

More importantly, however, is the fact that the TED app now has subtitles on its videos. You probably don't need us to tell you why this is great: not only do subtitles help out the hard-of-hearing, they're also beneficial to people who can't keep audio on while watching the video (like, say, people at work or watching on the train), or those for whom English isn't a first language. But actually, the subtitles aren't just limited to those who speak English—you can use the subtitles in a variety of languages.

“This release is a very important one to us. Our talks are translated by a team of volunteer translators worldwide. For the first time ever, their work is now available on iOS, our largest mobile platform right now,” TED’s Thaniya Keereepart said in a blog post. “The subtitle piece utilizes iOS 6′s new HLS services. Our engineers have been working very closely with Apple to make it possible.”

Tweetbot remains one of the most popular third-party apps for accessing Twitter, and the latest update to version 2.7 (actually, 2.7.1 if we're being specific) comes with really useful new features. The one that got us here at Ars worked up was the ability to open Twitter links in apps like Chrome and 1Password.

Here's the reason this excites us: few things are more obnoxious than clicking a link and being presented with a login screen. Only then do you realize that you don't know your password, thus forcing you to launch 1Password to get it, copy it, switch back to your Twitter app, and then paste it. Being able to open links directly in 1Password helps to cut down on that frustration significantly, allowing you to use Twitter with a password manager more easily. The same concept applies to Chrome, but from a different angle—the ability to open links in Chrome (as opposed to Safari) allows for more flexibility if Chrome is your preferred browser on iOS. No more copying and pasting URLs for you!

That's not all that got updated in Tweetbot, though. The app also gained the ability to display Flickr photos in-line as well as Vine "videos." There's also "better support" for muting tweets that contain URLs, for those of you who don't like Twitter turning into a glorified news reader.

Twitter (now with better search): free

Speaking of the devil, Twitter updated its own first-party apps for iOS and Android this week with a makeover to its search and "discover" capabilities. Admittedly the Discover tab isn't something I often make use of, in part because it had too many UI elements to browse through. The new Discover tab makes this feature much more usable—it unifies tweets, "trends" (hot topics on Twitter), and activities into one view so you can get a quick idea of what's going on among the general Twitterverse without having to hunt for it.

More importantly, however, are Twitter's tweaks to its search button—it's now available right next to the new tweet button in the upper right-hand corner. Twitter also claims the search "now shows the most relevant mix of people, Tweets and photos," and you can now access your five most recent searches in case there's one you perform often. You can also clear your past searches, for those of you who would like to keep your privacy.

Skype for iPad 4.5: free

There's not a lot new with Skype for iPad, but the reason it made its way into this roundup is because of one particular feature: the ability to add money to your Skype account directly from within the app. This seems like an obvious feature to have, yet Skype didn't allow it until this week's update. (When I faced this problem recently in Mexico, I had to go to the full Skype website on my iPad to refill my account before going back to the app to make the call.) Although this feature is currently only available to the United States, United Kingdom, Sweden, France, and Estonia, it's still a huge step in the right direction for an app that is dedicated to VoIP calling.

But aside from the ability to load up your account, there are a couple other worthwhile updates worth commenting on. The app's description says it can now automatically reconnect a dropped call in the event your cell or Wi-Fi connection dies—useful mostly if your connection picks up again soon after the drop.

Facebook (now with more A/V): free

Facebook continues to try to get between you and your cell carrier with this recent update to its iOS app. The most prominent new feature is the ability to include voice or video recordings within your Facebook messages, expanding on the media you can include when communicating over Facebook.

This may not seem exciting for some of the introverts on the social network, but members who communicate with families—especially those with kids—will undoubtedly appreciate the ability to include these sound or video bites in their messages. After all, tons of people are already on Facebook constantly—it's less about launching a new feature and more about keeping people where they already are instead of sending them away to another service.

And as an extra usability feature, Facebook allows you to record video or audio from right within the updated app—no need to switch to the Camera app or use something else that will save the video to your camera roll.

MyScript Calculator: free

MyScript Calculator was sent to me by Chris Foresman, who got it from our friends at The Mac Observer. Basically, the app allows you to write or draw calculations onto the screen using your finger or stylus, interprets the numbers and symbols, and spits out a numerical answer. (See the screenshot above for an example.) In addition to that, the app allows you to scratch through answers to make corrections without being thrown for a loop, and has video tutorials for those who need it.

The upside is obvious for those who think and solve problems visually: MyScript Calculator allows you to draw out the problem without forcing your brain to go into calculator mode. Though it's likely to be inefficient for complex calculating sessions, but this app is pretty cool, at least for simpler problems.

Listing image by Yutaka Tsutano