There has been a number of tutorials over the years about emailing your ideas into Scrivener via IFTTT and Dropbox. It’s pretty easy to set up, and IFTTT is a real nifty bit of kit. A bit mysterious to start with but pretty easy once you get the hang of it, then interfacing it with Dropbox and lastly Scrivener.
Care should be taken in following the popular online tutorial on the subject of emailing your Ideas to Scrivener, because Scrivener has changed somewhat since that tutorial was put up on the internet.
I will put a new tutorial up here when I get an opportunity.