The spread of smart mobile devices should make it unsurprising that the number of engineering apps for the iPhone continues to grow. Here, we stick with showcasing a few free applications (most also work on the iPad and iPod touch).

The handy Digi-Key app lets engineers search the company’s inventory of electronic components — anytime and anywhere. Users can search over 1.6-million products by part number, keyword, or category, learn about new products, and call the company directly just by clicking the Contact By Phone button. The app lets you know if a product is in stock and whether it’s lead free and RoHS compliant. Searching for “battery” as an example brought up several subcategories: Clock/Timing - IC Batteries; Memory - Batteries; and PMIC - Battery Management. After selecting Memory - Batteries, and tapping Search, 11 listings pop-up. Each includes the product name, Digi-Key part number, mfg. part number, quantity in stock, and unit price. Tapping an arrow next to the listing leads to a picture of the battery and other additional details.

The PocketCAS Graphic Symbolic Calculator lets users input formulas and manipulate math functions to solve almost any mathematical problem. A mathematical keyboard makes entering terms simple. Basic calculations work as expected. For example, typing-in 1+2*3+4*5 and then tapping the equation brings the results, 27. The program includes contextual help, tutorials, and lessons. For instance, a useful Linear Algebra tutorial shows how to work with matrices and vectors.

 Just about everyone needs a way to manage information. Evernote lets users type textual notes, snap photos, record voice messages, and save everything in the one app. Just click on New Note and options such as Voice let you start recording a memo and then save it with a single click. Snapshot lets you take a picture with the iPhone camera. To find saved notes, just tap on Notes and start scrolling. Or, tap on the i to change how the notes are categorized as, for example, by city. Create an account using the app, then go to the Evernote Web site, and all your notes show up on your online page. (The desktop, iPhone, or iPad app, and the Web site are said to all sync.)

Handy for engineering calculations, Kgm2 - Weiss Inertia Calculator 1.0 lets users type-in the dimensions of an aluminum or steel block or cylinder to get the shape’s mass inertia.

Admittedly still in rather rough form, iMachinist 1.1.3 aspires to be a “community driven machining/engineering calculator.” If you don’t see an equation you want, just email the developer via Formula Submissions and he will add it. The app currently includes common machining formulas used by CNC programmers as well as an-inch-to metric converter. Shop Math is soon to include a trig calculator.

 Want to view stereolithography (.STL) files on-the-go? netfabb Mobile lets users download files from the Web or from netfabb Studio, the developer’s desktop program for creating and repairing .STLs. The mobile app includes a Color settings option which lets you change model colors with sliders for red, green, and blue. Tapping a cloud-shaped icon brings up netfabb’s Cloud Services, a free way to check and repair files. Upload your file by entering your email address. The service checks for errors and buildability and sends a return email with a link where you can download the repaired version of your file. Note that Cloud Services is in beta and cannot handle all .STL files. It thus directs users to check-out the free desktop application, netfabb Studio Basic.

And speaking of CAD data, how about the capability to not only view but mark-up, edit, and share .DWG files? Think AutoCAD WS. To upload .DWG files to your iPhone, first sign in to the AutoCAD WS Web site from a PC and click Upload drawings. Open the iPhone app to view the file, or add elements such as circles, polylines, lines, and rectangles to the drawing. A markup icon lets users add comments inside of a rectangle, cloud shape, or text box. You can even make comments via a pencil tool, which lets you draw a free line. Undo and redo arrows are handy for correcting mistakes. A nice feature: the program automatically saves changes as you work. A Help section explains such things as how to open .DWG email attachments and how to share drawings.  

Authored by Leslie Gordon