Samsung will roll out its Expert RAW app to a number of devices in the course of 2022. The beta app has been available for the Galaxy S21 Ultra since November, and can be installed on the new Galaxy S22 phones.
The rollout will see the S21 Ultra will get the official app in March. The Galaxy Z Fold3 will follow in April, while the S20 Ultra, Note20 Ultra, and Z Fold2 will get Expert RAW in the first half of the year.
If you want to try Expert RAW on your Galaxy S21 Ultra, you could just download the APK from somewhere and install it. It works just fine.
Expert RAW gives you a higher-fidelity DNG file along with Samsung’s HDR multi-frame processing applied. It works with all four cameras on the S21 Ultra. You can then push the files in Lightroom to change White Balance, colors, exposure, and whatever else you’d want. Just keep in mind you need to apply Samsung’s profile in Lightroom in order to get the HDR processing.