cryptomator is the best app available on cross platform. it is free and open source software , faster encryption than boxcryptor. also here is a basic video which shows How Cryptomator app works on android and how neat and clean UI it has.
Here is the link to that video https://youtu.be/1jLS5R4gbhw
look how You should use cloud storage + cryptomator
**1- use cryptomator with Dropbox (both supports block level sync dropbox and cryptomator) **
2- Use Sync/Mega app to have backup those files you upload on dropbox using cryptomator. if something wrong happend then you always have a backup copy . this is the best way to use cryptomator .Sync cloud is the best cloud app to use in iphone. I personally use cryptomator with dropbox and sync cloud for backup if anything wrong happens with cryptoamtor.
@SailReal bro what’s your opinion on my method “How to use cloud storage+cryptomator”?