You have to spit your mobile screen in two if you want to see citrine working. 
On my phone if I hold down the button the far left and it will spli my phone in dual screen. 
So citrine will be on top and amethyst will be on the bottom. 
I can see citrine working if Amethyst is open but as soon as I close Amethyst, citrine stops working. 
Before splitting my screen I was confused at first because I thought it wasn't working.

I like citrine I hope they keep developing and adding more features. I want more control over my posts and the ability to download and restore instead depending someone's relay.