U.S. President Obama holds up his iPad during a visit to TechShop in Pittsburgh
U.S. President Barack Obama holds up his iPad with a photo of him hugging his daughters during a visit to TechShop in Pittsburgh June 17, 2014. The iPad's case, a Dodo case, was first designed and prototyped at a TechShop facility. REUTERS/Kevin Lamarque

The app that was designed to get extra use from the iPad was invented by Rahul Dewan, an engineer who served at Apple for three years on the iPad and iMac project. According to Dewan, having a second display for the Mac can increase productivity for up to 48 percent. Duet can also deliver a retina display at 60 frames per second absolutely with no lag. Owning an iPad together with the application allows interaction with OS X and the iPad as an advanced second display for Mac.

The extra screen brought by the app is beneficial for musicians, designers and photo-video editors. Duet Display also takes advantage of iPad's touch capabilities, which allows users to tap and scroll through and drag over to the second screen.

This is not the first app that turns the iPad as a second display, apps like the Air Display also works just the same. However, the Air Display connects the iPad to the Mac using wi-fi which results to lagging, unlike Duet Display which is connected to the computer using the iPad's charging chord. Duet performs with zero lag and results to a true Retina resolution which makes full usage of iPad's HD display, Business Insider reports.

The app which is a product of ex-Apple engineers, also offers energy saving options for owners of the not so powerful and older Macs. The user can opt to choose between the regular and Retina resolution, but user needs a newer Mac for the Retina to function seamlessly. The user is also given the option to switch between a 30Hz or 60Hz refresh rate.

Interested Apple users can easily set-up the Duet Display by just downloading the app on the iPad. Just connect the tablet to the Mac then restart computer and everything is all set. The app works in both portrait and landscape mode.

Duet Display was just recently launched and is already available for download. The app is compatible to all iPads powered by iOS 5.1.1 and above.