Meet the Accsoon SeeMo: a neat gadget that turns your iPhone or iPad into a professional monitor. It also supports streaming to Twitch, Facebook Live, and YouTube using RTMP. The SeeMo combines with the Accsoon SEE app to give you access to common features such as grids, focus assist, zebra, and histogram.
The Accsoon SeeMo has a quick-release modular design. It is powered by a Sony NP-F type batteries. You can use this to power microphones, on-camera lights, and other devices with a USB-C out port.