Is it possible to take pictures for a timelapse on a Nikon D90 without using an intervalmeter

There are several inexpensive interval timers, around $20 US or less, so there is hardly any reason not to get one.

Here is one for D90: https://www.amazon.com/Neewer-Digital-Shutter-Release-Replacement/dp/B005LTH7QA/ref=sr_1_3?dchild=1&keywords=mc-dc2+d90&qid=1592431501&sr=8-3

This is seemingly a knock off of the Nikon MC-36a timer that is $160. Or possibly the same chip in it now? This same item comes labeled as several brand names, and with connecting cables for different cameras, and most of them are not over $20. The D90 uses Nikons MC-DC2 cable, so the timer should specify MC-DC2 or D90.

Please do research beforehand, here is a link to a YouTube video that uses an android device to control time lapses. I hope that answers your question.

Frame challenge…

How long is your total time-lapse to cover?
Intervalometer, tenner from eBay, batteries will last months. Phone/PC, [even though you already own them] batteries will last ~1 day.
Also - what happens if your phone rings?