Any remote shutter device that is compatible with the d3x00, d5x00, d7x00, d6x0 series of cameras should work as they use the same connector.
You may want to post links of ones you like that meet that criteria.
EDIT: OOPS .. read post below .. apparently the D3400 dropped the USB port ?!?! making it even more of an entry level camera.Hello!
Wondering if anyone can confirm with first hand experience if an intervalometer designed for a Sony A7 actually works on the Nikon D3400?
I actually emailed Vello about their shutter boss unit for the Sony A7 and they didn't deny it would work but said they cannot guarantee it functioning 100% as they haven't tested for it.
I've been searching high and low for a wired solution for my new D3400 but am struggling with this USB port...