The Elements ★★★★★ ($9.99/ App Store) for the iPhone and iPad is an interactive periodic table app. Sounds boring but once you actually use the app, you will realize how interesting the elements are even if you never cared for science. Having a massive download size of 1.21 GB, this app contains a significant amount of detail and movable element images in satisfying HD. If you can spare the space in your iPhone or iPad and have the slightest interest in science, The Elements by Theodore Gray is well worth the cost. 

Canabalt ★★★★☆ ($2.99/ App Store) for the iPhone and iPad is a classic one-button endless running mini game. You play what seems to be a master runner and jumper hopping from buildings to cranes to skyscrapers to billboards in a mad rush with random obstacles coming at you. Despite the fact that there is only one button and requires aw single finger to play, the intensity and excitement is on par with frantic first person shooter games.  

Calcbot ★★★★★ ($1.99/ App Store) for the iPhone and iPad is a robot calculator. Okay, so its just a calculator - but the finest one in the App Store, far exceeding the built in iOS one. From the makers of [Tweetbot] and [Convertbot], Calcbot is extremely well polished, the user interface top notch with sound effects to match. Other than that, Calcbot features a live type-as-you-calculate expression view with history. Swiping to the left slides the advanced calculations area. No doubt the best calculator app for the iOS. 

Word Lens ★★★★☆ ($.free / App Store) for the iPhone is a real time video camera language translator. Point at a sign, menu or most readable text with your iPhone camera and Word Lens will magically translate those words right on the image your viewing from! It works as advertised. But this is one of those apps people give bad reviews to because they don’t read the entire app description before downloading - the app is free and will work on reversing words but the actual translating costs $9.99 from Spanish to English and vise versa. While it seems expensive, its not because of how well it actually works. 

Photoshop PSD Viewer ★★★★☆ ($.99 / App Store) for the iPhone and iPad an app that lets you view Photoshop documents (PSD). Not even the Photoshop Express iPhone app can do this! This could be an immensely useful app for designers or anyone needing to view PSD files on their iOS device. Files can be via mail, Safari, Dropbox and all other external utilities. Shows in CMYK, RGB or CIE lab colors with zooms to 1000%.

Speed Tracker ★★★☆☆ ($1.99 / App Store) for the iPhone is a GPS speedometer and trip computer. So it tracks and shows in real time the speed you are moving, the time it takes to get from locations and the distance traveled. The user interface is fairly well done and looks like what a modern speedometer should but is not accurate enough of the time. While this may be due to hardware limitations, an app that specifically is made to measure things should be very accurate.