You can simply put your file in Google drive and work with it simultaneously from different devices: https://community.alzex.com/knowledge-base/article/sync_mobile
There was sync through Google Drive just like Dropbox, but it worked awfully. Google Drive has many bugs, it can simply stop updating data. It also has some “strange” features like possibility to have several files with the same name in one folder. It’s API is complicated and buggy. All this makes it completely unusable.