I like metaphors, so try this one. When a baby is an expert crawler he/she can move pretty fast. When he/she makes the transition to walking the movement is less efficient and the child moves slower, often even dropping to the floor to crawl when walking feels too slow. But over a few months the baby learns to walk well and then run. This is what digital feedback feels like for teachers, slower at first, and then much much faster.
Five tips to help you:
Have students share their work early: With digital writing students can share their work while it is still in progress. You don't have to wait for them to turn anything in. You can look at early drafts sooner and give feedback students will really use. This is a huge advantage over paper methods.
Learn the comment hot keys: I use Google Docs, so when I want to add a comment to a student's paper I just place my cursor on the word or highlight a sentence and then hit Ctrl+Alt+M. This instantly opens a comment box on the side that I can type my feedback into and then I hit Ctrl+Enter to close the comment. This saves me a few seconds per comment, which isn't much, but over the course of 180+ essays a few seconds really adds up. If I save 60 seconds per essay I get back 3 hours.
Use suggested edits: Google Docs gives me the option to switch to suggesting mode. By using suggested edits my changes show up in another color and add a comment to the side as well. I can even add on to the comment to explain the suggestion. Students have to either accept, or reject each suggestion. I can use this to show a student a pattern of errors, or add a sentence frame I'd like to use to support them.
Use Google Keep for comments you use a lot:Google Keep is the yellow lightbulb icon on the right side of Google Docs. Click that and you can add notes and then open them using the lightbulb in the next document. When I am grading an assignment I'll collect my comments in a Keep note and then I can easily access them in the next student's paper. A quick copy/paste means I don't need to retype that comment. (Learn to use Ctrl+C and Ctrl+V to copy/paste even quicker.) Keep notes can only be shared with individuals, but I can share a doc with some common comments here. You can even include links to tutorial videos in your comments.
Feedback Extensions and Add-Ons:
Several extensions in Chrome can help you give faster feedback. Checkmark creates a menu that pops up whenever you highlight a word. Click a box in the menu and it adds a comment to the student paper. (Note, this menu gets a bit annoying if you aren't giving feedback, so it's good that it has an easy slider option to disable it.) You can even customize the menu and the comments. You should also take a look at Kaizena, and Joe-Zoo, and OrangeSlice. One or more of them may be just what you need.
Use Doctopus and Goobric: Doctopus is an add-on for Google Sheets. It's a little advanced technically, but it can save you a lot of time if you want to grade student work on a rubric. With Doctopus you can "ingest" an assignment from Google Classroom, and then attach a rubric with Goobric. This will make it possible to open each paper in a window with the rubric already at the top. This makes rubric grading much faster. The learning curve for Doctopus and Goobric is steep, but once you master this, you'll save yourself so much time. I made a tutorial video about how to do this.
The great thing about giving students digital feedback is the speed. You don't have to wait for them to be "done" so they get formative feedback sooner. Also, students can see your feedback without having to wait for you to pass back papers. Now that you have devices you'll also want to explore the fabulous possibilities with peer feedback. I wrote this post about Writing Response Groups to help you with that.