The new version 7.4 of Filmic Pro has recently been released. Another professional feature of the camera app is the LUT import. Up to 7 LUTs can be loaded, supported are .cube LUTs up to 64pt (iOS) or 65pt (Android). The LUTs can either be activated normally for the preview, or if desired - if it should go fast - also be applied directly to the recorded video clips.

Filmic Pro 7.4 LUT import

LUT selection
Import is done via the Imaging panel, where there is a new tab for LUTs (colors and gamma are now combined on one tab for this purpose). If the LUTs are on board, the easiest way to select and deselect them is to assign the LUT functionality as a Quick Action Modal (QAM) to one of the six freely assignable touch keys.
Since version 7, Filmic Pro is only available by subscription with a not very clear pricing structure. Current pricing appears to be about .99 per week or .99 annually (plus Cinematographer Kit).