I have used Dropbox and OneDrive for online cloud needs but I find Google Drive to be the most convenient. Notice I didn’t say best – it may or may not be but I know it is the most convenient given that I use the Android ecosystem for my phone and tablet. I am deeply integrated with Google apps such as Photos, Docs, Keep, Sheets; so it is just convenient to backup my documents and pictures using Google drive. I automatically backup my photos and documents to Google Drive. I have had no complaints with the service and the App. I have 19 GB and I am at 60% usage. I will update to about 100 GB within a year as my data needs have been increasing exponentially. I am logging all receipts and transactions electronically and that adds over over the course of a year.