I need your suggestions and tips on how to do time-lapse photography without using an intervalometer; I am using a Nikon D3300.
You can use your usb cable and connect your camera to the PC, and then use Shell script to shoot with. I used this to shoot HDR timelapse ( https://www.youtube.com/watch?v=dQFYTRffuPc&spfreload=10 : I was just playing around ). What you need is an unix like OS, then library like Gphoto, cable which came with your camera, tripod, and simple shell script where you tell camera to take photos at precise intervals, in this way you have complete control over your camera ( if it is supported, which I believe is ). If you like, I could post that script & tutorial on my webpage.
Finally I connected my moto g3 mobile with my nikon d3300 through OTG cable. Then I used an app called DSLRDashboard. It worked. Its great to control my camera through this app. It almost does everything.
Link to download the app: http://dslrdashboard.info/
If you have an smarthphone with IR Blaster like Note 4 or Galaxy S5, you can use an App called DSLR Remote to take pictures on your Nikon 3300 every time your phone send the signal according to the settings you pre-configured.