App: Advanced Task Killer

Creator: ReChild
Type: Productivity
Description: If your phone starts running slow, you should download this app to kill tasks that you do not need. Advanced version has options like auto kill and ignore list so once you set up rules you're good to go. If you want simpler version (tap on app to kill) than try Lite version of this app.
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App: Inventor Publisher Viewer

Creator: Autodesk Inc.
Type: Productivity
Description: This is app for Inventor publisher's users. Enables you to preview models you've made on your desktop computer.
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App: Android Pro Widgets

Creator: Dr. Appche
Type: Productivity
Description: Pack of various widgets for Agenda & calendar, people, bookmarks, messaging, facebook and more.
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App: Microsoft Tag

Creator: Microsoft Tag
Type: Productivity
Description: I guess this is Microsoft's rival to QR codes. Scan Microsoft tag and acces info, videos, and other material online. It also gives you a visual history of your last 15 Tags and allows you to flag and organize your faves.

App: QR Droid

Creator: DroidLa
Type: Productivity
Description: If you still do not know what is QR code you might read this wikipedia's article about QR codes. Now, this is not just another QR code reader; firstly, when you scan code built in previewer will show you brief info of data stored in code. You can also make your own QR codes, and even implement your logo in it (example in screenshot section). There are also default action rules where you choose what to do when certain type of info is scanned. It also has some cool features like encryption of codes, generating QR codes with your contacts data and scanning codes from image file or URL. Very intuitive and worth downloading.
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QR Code: