The Roundup is back, and more artistic than ever with one of the most stunningly beautiful games on a mobile device.

After a brief hiatus, the Android Market Roundup is back like that nagging cold you've been battling for the last two months. The Roundup is not known to cure the common cold, but we suspect it's about as effective as most of the pills that make such claims. So your nose may be running, your lungs congested, and your throat sore, but at least you can get some cool apps. Just scan the QR code with Google Goggles or Barcode Scanner to go straight to the Market. Alternatively, click the app name for a link to the web Market.

This week we're looking at a beautiful physics game, a fountain of knowledge, an addictive puzzler, and more. Let's start small, and absorb the competition.

Some games are fun to play, some have great controls, and some have stunning visuals. Ideally, you want at least a hint of all these in your mobile games. Osmos HD possesses all three qualities in abundance. It’s at once both relaxing and intense as you maneuver your tiny cell through a swirling microcosm rife with danger. The only acceptable excuse for why you’re not playing it right now is that you want to read the rest of the Roundup first.

In each level of Osmos HD, you begin as a small spore-like spherical cell. Tapping on the screen will cause your spore to launch a tiny bit of matter in the direction of your press. The realistic physics engine in Osmos knows its classical laws of motion, and the corresponding effect is that you are propelled in the opposite direction. Tap a few more times, and you pick up speed. You also lose mass each time you eject matter to move, and Osmos is all about how massive you are.

You can absorb any cell that is smaller than you; these will be totally blue, or red with an outer layer of blue if the comparison is close. Each orb that you consume makes you bigger, and gives you more fuel to jet around. In most levels, you have to reach a certain size, or consume a special cell to move on.

The physics implementation in Osmos is one of the best we’ve ever seen. It uses game mechanics that are not immediately obvious, but extremely satisfying. For instance, if you eject some matter into a larger stationary cell, it will start moving slowly away from the point of impact. Sometimes you need to do things like that to make your way, and the game might feel a little slow as you wait for physics to take its course. But don't fret, the game includes time manipulation. Swipe left and right to slow and speed up time. Even the menu functions are well-designed, relying on multtouch tapping.

The graphics in Osmos are absolutely beautiful, consisting of contrasting dark backgrounds and bright foreground colors in the cells. There are subtle lighting and particle effects that don’t distract from the clean lines of the game, or the smooth animations. We saw not a single hiccup on the Galaxy Nexus, and on an AMOLED screen, Osmos is especially stunning.

Oh, and the sound. Gorgeous. Osmos suggests headphones, and we’d agree. It’s all composed of gentle, unhurried beats with lovely ethereal melodies. You feel relaxed settling into a game of Osmos HD. The tracks also work perfectly at a faster tempo when you speed up time.

The only complaint we have, is that Osmos HD will suck your battery dry in a big way. If you’re not using your device for much else, just and hour of Osmos here and there throughout the day will put you in the red before you know it. Luckily, the levels in Osmos are great for a quick play, so you don’t have to devote a ton of time to each session. Osmos HD is selling for $4.99 and you need this game on your phone right this instant.

Trey Ratcliff is a phenomenally talented photographer who’s work you have probably seen without knowing it. Now you can get an endless stream of Trey’s beautiful pics on your phone with his new Photo Voyages app. The app itself is simple, and lets the photos speak for themselves, but it offers you the ability to not just view, but share and set images as wallpaper.

We won’t talk too much about the artistic value of the images produced by Trey Ratcliff except to say we like them. There are a lot of skylines, architecture, nature, and clever perspectives. Many of the shots are done in HDR, but subtle and attractive HDR. Not that overwrought, ham-handed stuff you’ve seen elsewhere.

When you open the app, it will act like a slideshow, rotating the picture on screen every few seconds. You can also swipe through images manually. There are a ton of pictures avaialable, too. When you find something you like, just open the menu and choose to set it as wallpaper. The app will load the cached picture into your system Gallery cropping interface. You can also share links to your favorite images.

Unfortunately, there is no way in the app to save an image directly. You have to use the share link to get to Trey Ratcliff’s site and download the image. Although, he does make the super high-resolution version available if you want it. Even the files pulled down on the device are big. In fact, the app will by default stop you from using 3G/4G data to get images. You can change this in the settings, though. The settings also contain a options to change the slideshow timing and transition effect.

The app is a little buggy, with an occasional lag in loading images, or a rare force close. Most of the time it works quite well for us, though. This app costs just $0.99, which we think is a small price to support a photographer and get some of the most stunning backgrounds out there.

This isn’t your typical RPG. This is an RPG played by way of an ever-changing puzzle filled with baddies. Dungeon Raid has been on other platforms for a while, but the Android edition was well worth the wait. Don’t be taken by the simple look, it’s a surprisingly fun game for a low price.

In Dungeon Raid, you will be confronted with a 6x6 gameboard filled with various icons. Coins are used to buy upgrades, shields increase your defense, potions heal you, and the weapons are for attacking. There are also enemies that will attack if you don’t clear them off the board. Each turn, you need to draw a line through a number icons to make your move. You can go in a straight line, but also use diagonals to meander around the board.

You can only activate a single type of item each turn. Maybe you want to grab some coins, then attack the next one. Perhaps after that you want to pick up a few healing potions. The effects go up the more of the matching icons you can connect, but you might want to ration your resources. If you have a lot of weapon tiles, but only a few enemies, don’t build up a 20HP attack; save some for later. When you clear a tile, everything sinks down and more items drop in from above.

As the game progresses, the enemies that show up will become more hearty and do more damage. You have to use the coins you get to upgrade your abilities, and buy special powers to make it through. Do well, and you unlock more character classes, items, achievements, and more. This helps to keep the game interesting after the initial newness wears off.

You just play turn after turn of Dungeon Raid until you’re defeated. Then you can start over with a new class, or try the same configuration again. We really like that the game has flawless state saving. You can play a few moves, hit the home button, and come back to it the next day and just pick up where you left off.

The graphics and sound are obviously very simple in Dungeon Raid. It has a nice clean style, and the interface is easy to follow. It’s really the gameplay that makes Dungeon Raid what it is: seriously addictive. The game offers so many ways to play that it transcends the superficially simple concept. Dungeon Raid is just $1.99 in the Android Market and it’s good for hours of fun.

At long last, the official Wikipedia app has arrived on Android, and it’s actually very good. Not only is it a slick interface for the web pages you can already get in the browser, the app adds some great native features like offline viewing, local search, and easy language switching.

The app will open to that familiar page with a daily sampling of content from Wikipedia. You can tap on links to read more about various subjects there, or use the search box at the top of the screen. This search box is persistent throughout the app so you can easily jump to other pages. Page loads and scrolling are both very smooth in the app.

While on any page, you can open the menu and choose to save the page. This is a very handy feature if you’re going to need to reference an article later. The saved page will be downloaded in its entirety for offline viewing. There is a separate menu item for viewing your saved pages. Any pages you no longer need can be deleted with the ‘X’ on the right of the list.

Also in the menu is the Nearby feature. This will bring up a Google Map of your local area and search for points of interest on Wikipedia. Tap on any of the small blue flags to get a preview pop up of the site, and tap on that to load up the full page. This could be very useful when vacationing, or just poking around your own backyard. The Wikipedia app is free, and it’s pretty cool. There’s no reason not to get it.

Side-scrolling shooters have never been so fast, or frantic as in Stay Alive. There is no real goal in this game other than to go very fast and make it to the finish line in one piece. You need quick reflexes, and snap judgement to stay alive in Stay Alive. It’s no walk in the park, so only the serious mobile gamer and those with a high tolerance for failure should proceed.

Your small but scrappy ship will stay off to the left of the screen as you shoot through space. Slide your finger up and down the left side of the screen to steer the craft, and tap anyplace off to the right to direct a blast from your cannons in that direction. We like that the weapons don’t just fire directly in front of you, but that you can choose where the projectile goes.

Most of what you encounter are space rocks that will batter your ship. Your weapons will vaporize everything in your path, but you can’t go firing all randomly; you have a limited number of shots. As you weave through the level, there are orbs to pick up. These can be spent to upgrade you ship, which is a necessity if you’re going to finish the game.

There are 21 levels, and they get harder as time goes on. Enemies will begin to show up more frequently, and it can get hairy dodging enemy fire and space rocks at the same time. If you can’t make it, you can restart the level as many times as it takes, but you get to keep the orbs collected in failed runs. Most of the levels are over in under a minute, though.

The graphics are reasonably good in Stay Alive. It’s not groundbreaking, but it is a solid effort. The lines are smooth and free of aliasing, and the simple silhouettes work well in the game. You wouldn’t want a game this fast to have too many complicated textures; it just would’t be clear.

It might take a little bit to get comfortable with the fast pace of Stay Alive, but once you sort out when to shoot, and when to dodge, it’s fine. The Pro version of the game costs $1 in the Market.

That's the Roundup for the week, folks. Hopefully something here struck your fancy. If you've got an app in mind for a future Roundup, let us know. Check back next week for more great apps.

P.S. - Hi Redditors. Stay a while, why don't you?