[XDA Assist] rtorresz:
A friend of mine just dropped her phone and the LCD stopped working (no cracks, tactile was still working), her phone (Oneplus X) was running stock, unrooted and USB Debugging was disabled, so none of the available solutions were useful in this case. I almost lost hope after reading everywhere that there was not much left to be done when USB Debugging was diabled, so I tried a different approach.

There are a bunch of software that claim they can recover data but they all need USB Debugging to be enabled, so this was a big barrier. After a few tries I finally came up with a solution that I think can help anyone facing a similar situation. In my case I did all this blindly tapping on the blank screen, if your screen is more damaged you can use an OTG cable and a mouse or keyboard, you can find more info on this in other threads.

Step 1: Connect to a WiFi Network

First I needed to connect the phone to a wifi network, which I managed creating an unprotected network with a freshly installed DD-WRT router and clicking blindly on the phone. We all have a mental image of where things are located on the phone so this should be easily doable (slide from the top, tap to enable wifi, long press to see list of available networks, tap to select network) and if you are sitting next to the router the unprotected network will appear first in the list. On the router check for connected devices and the IP of the phone. A ping test will confirm that the phone is succesfuly connected to the network.

Step 2: Install AirDroid

Fortunately when I received the phone it had already installed Airdroid, so this made the process a little easier for me. The first time you run Airdroid a couple of extra screens will appear trying to get you to subscribe to access all the extra features so this will make things a little more complicated for those installing for the first time, try to google these images so you know whre to tap. I understand there are other apps with similar functionality but the fact that Airdroid starts with an A is very helpful here because it shows (at least for me) on the first row of your Apps Drawer.

Step 3: Connect to Airdroid

Now it's time to connect to AirDroid, to do this you need a computer connected to the same wifi network that the phone is connected, and since you already know the phone's IP this becomes a process of trial and error. Again, blindly tapping on your phone access the Apps Drawer and start the app placed on the first position (upper left corner under the search bar), in your computer's browser type the phone's IP followed by ":8888" (192.168.1.143:8888 in my case). If you fail to open AirDroid the page will just time out so you go for the app on the second position and reload the page on your browser, then the third and so forth.... once you successfully manage to open AirDroid a page will finally load and you'll hear a notification from your phone (it was the fourth try for me). Now there should be a notification window waiting for your confimation on your phone (google this to see where it is) so it shoud be an easy guess on where to tap. Once you can access your phone via AirDroid, the hard part is over! Now we can download pictures, files, ringtones and other stuff, but if you want to backup contacts there's no tool for this so we need to enable USB Debugging.

Step 4: Enable USB Debugging

With AirDroid running we can now take screenshots of the phone with the hardware buttons and view them using the "Photos" folder in AirDroid, so you open the notification drawer and tap where the "settings wheel" should be, take a screenshot and view it to confirm you succeeded, then scroll all the way down and take another screenshot to se if "Developer Options" are enabled. I'm sure by now you get the idea of the process, after any tap or scroll take a screenshot and view it to confirm your progress, once I got Developer Options enabled I managed to scroll down to USB Debugging and to enable it!

Now with USB Debugging enabled you can use programs like MyPhoneExplorer to backup your contacts to a .csv file or use screen cast apps like Vysor to see your phone's screen on your computer vía USB.