Monitor+ is a free iPhone application developed by HON IN UN. It allows users to transform their phone into a professional camera monitor instantly. With Monitor+, users can connect their iPhone to compatible Sony cameras wirelessly or through a wired USB connection.

The key features of Monitor+ include live view, remote control for settings such as shutter speed, iris, ISO, and white balance, touch autofocus, and display focus point. Users can also record and playback live view signals, access various assist functions like false color, zebra, waveform, histogram, vectorscope, guide, focus peaking, desqueeze, and LUTs (available on the Pro version).

Additionally, Monitor+ offers features like chroma keying and overlay, focus pulling, an Apple Watch extension, and screen lock. Please note that some of these features are only available on the Pro version.

It's important to mention that Monitor+ is not affiliated with Sony Corporation and is not a Sony product. "SONY" and "Sony" are trademarks of Sony Corporation.