Possible to hide crypted folder and its content?

Hi,
I am using CM1.6.17 on Mac and want to share the vault with iPhone and iPad via iCloud.
On mobile devices I use the version 2 of CM.

In order to protect the crypted data stored in iCloud from accidental damage, I created a vault with name “.invisible” on my iCloud Drive. This works well with the Mac.

However I cannot connect to such a hidden folder with iPhone, nor iPad, as I found no way to type the directory name.

It would be great, if mobile app could also import hidden crypted folder vaults.

As I plan to share the iCloud Drive within family, and I do not want data to get corrupt by somebody unintentionally changing the crypted directory structure, this would be a nice feature. Read-only is too strict for me.

Or did I miss another way to protect my data?

Is there anybody here with an idea?