Duet 2.0 is hardware accelerated but still completely software. This means the GPU can handle more of the work, saving CPU resources & battery life, while increasing responsiveness.
Yes, if we look at Duet Display's reviews on Apple's App Store, it does seem that most customers are pleased with their purchase and find that it was a worthwhile investment in increasing their productivity.
It is ranked #32 among Productivity apps, and out of the app's 31.3K customer ratings it averages out at 4.4 out of 5 stars.
Yes, Duet Display is safe, as it uses 256-bit encryption and works entirely locally, keeping your display data safe.
No, Duet Display is not free.
According to their site, Duet Display offers two pricing plans for regular consumers. Their basic option, "Duet Display" is a one-time purchase of $9.99. This plan allows you to use your iPad as a wired display with basic touch control. Their more premium option, "Duet Air" is an annual subscription of $19.99. This plan has more bells and whistles, incuding improved performance, pixel perfect rendering, advanced gesture control, and the ability to use your Mac or PC as a second display. Finally, there is an Enterprise plan with custom pricing for larger organizations that can benefit from bulk pricing.
Duet Display is an app that lets you turn your iPad, and other mobile or tablet devices, into a second monitor for your Mac and PC. Developed by ex-Apple engineers, Duet Display is an easy way to turn your iOS or Android device into a high performance second display, all without lag. Duet Display was awarded #1 Product of the Day (and week, and month) on Product Hunt on December 18, 2014.