It will force close if you don't do the following steps: click and hold on the icon to let the "3d" menu comes up and chose take a selfie, the app will run. Then go to the settings, set to pixel 2 xl for the model, and the hdr+ set to auto, jpeg quality to 100% and hdr+ to super high. Close from memory, force stop it, and then clear cache. Run the app again and it will work fine It is a tad dull, and indoor it looks warmer, and outdoor slighter blue than stock. But images are much more saturated in color.
Alright, this OP has been updated to include FINALLY a working version of Gcam for the Snapdragon variant of the S9 Plus! https://www.celsoazevedo.com/files/a...n_v2.8_Exy.apk. Thank you so much for Idan, and his incredible work. All gcam prior to this suffers horribly on white balance until now. I have been testing rigorously with IDan and providing logs. The only thing to change in this version is set your exposure to X8 or X4 depending on your preference, change hdr+ processing to Pixel 2017, front camera to Pixel 2 XL. Front portrait some times work but it lags badly, and also front hdr+ normal camera sometimes crashes as well. This is not a stable version but it is the best version and it's amazing compared to stock now.
Hopefully soon IDan can get the portrait right