We have found 2 software records in our database eligible for .psd to .psdx file format conversion.
PSDX files are used by Photoshop Touch version for tablets. You do not need to convert psd to psdx to open in Photoshop Touch.
Upload your PSD file on your desktop to the Creative Cloud. Then on your Photoshop Touch, click New From ► Creative Cloud. From there you can open up psd files on your tablet directly.
However, the layers in your original psd files will be flattened.
It should be quite possible to simply re-save PSD format to PSDX with Adobe Photoshop CC. But the .psdx files must be smaller and easier to read due to mobile phones and tablets performance.
PSD
A psd file extension is traditionally associated with default graphic format of Adobe Photoshop. Adobe psd graphics file is pixel based graphics file format. However some graphic elements can be stored in vector graphics. In default psd graphics file contains layers with masks, color spaces, ICC profiles, transparency, text, alpha channels and spot colors, clipping paths, and duotone settings.
PSDX
Files with psdx file extension can be found as graphics saved using the Adobe Photoshop Touch software.