I write by hand the base idea, after that, I transfer it to my laptop in Word and polish it out. Then I translate it to English and before I post it I run it through Grammarly. 
Nothing special here.

I'm quite new here, so it's somewhat reassuring to read that I'm not the only one using Google docs. As has already been said, switching between laptop, desktop and mobile, which I do quite a lot,is effortless.

I do use grammarly in conjunction to avoid doing any silly mistake.

For the novel I'm currently publishing I just use docs and Google spreadsheets. This last one to tracks the different stats and their progression.

However, I'm writing a much more complex novel, with quite a few connections and turns. For that, I also use draw.io

It is really useful to draw flow charts, which I lay horizontally and use as a timeline. I can pinpoint when a skill will be learnt, where the MC will meet an important character, etc. Plus it makes it easy to keep track of everything, a simple zoom out and I see all the important pieces highlighted in a stronger border width and color.

I use Google Docs. I used to write exclusively with paper back in ye olden days when I was a youngster, then retype it to MS Word. Definitely increased my typing speed and touch typing skills that way! After losing at least 10 stories and the notes for many more in a harddrive catastrophe, I've learned to enjoy Docs. It's also nice for my project since I have a co-author/editor - we can work on document simultaneously and not worry about comparing versions. Mobile access is a huge plus as well!

I actually have two programs I am using to write. Nimble Writer and Campfire Pro. Nimble Writer being the actual writing software and Campire being a god send of a note software. Though Campfire Pro is costly if you don't catch it on a massive sale.

Google docs. I actually learned how to use it just for my current writing project. I was using Libre before.

LibreOffice - I like the flexibility, plus it's free, and it can do pretty much anything MS Office can (at least, anything I'm aware of).

I create a spreadsheet file for each project with tabs for various notes - character list, places, chapters, timeline, whatever I need for that one - so it's all in one place and easy to find.

I'm obsessive about making backups on both thumb drives and cloud storage, because I've previously lost data both ways.

Old system, which I often miss, was to use pen and paper and then the typed version became a second draft. Because I never throw away anything I've written, that actually turned into an issue as far as storage space. Also, it was a royal nuisance if I realized that I should have done something very different 30 pages back that changes everything from there on. It did, however, draw a clear line: when writing longhand, I could just let the story flow. Once I was at the computer, it was time to get serious.

I use Scrivener. It's a bit pricey, but it's an excellent one-time investment if you're hardcore serious about writing imo 

The website "https://writer.bighugelabs.com/" Is simple and distraction free, I find it very compelling to use. It's free too!

I write in Notepad++