I’ve been a Windows 10 Cryptomator user for some time now and very happy!
I just started using the Android version today and saw I could upload individual files, create text files, create folders, and delete things. But I was very surprised to see that there is no option to upload folders. Also you can only upload single files one at a time.
Are there any plans to eventually support upload of folders and/or multiple files to the Android version?
Welcome to the Cryptomator Community 
there exists a feature request on the android issue tracker:
Unfortunately, it won’t be implemented soon.
You CAN now, upload multiple files at once. I just did it as a test. Choose upload a file and then long press the first file until it becomes selected and then you can select a second and third and fourth file Etc and then it will upload all at once.
Great! Any word on uploading folders under Android?
Thanks for making multiple file uploading a reality! 
I know nothing about it. Somebody else mentioned not to expect it anytime soon.
If you have a large folder of files that you would like to upload you can use a zip program on your Android and put the entire folder into a single zip file and upload the file that way.