Is there a way to have 3 apps side-by-side in split view?

Not in full screen mode, but you can easily create an arrangement of 3 (or as many as you like) windows in Terminal (and not just side by side, see below), and save it for reuse: give it a name, and recall it from the window menu:

Here is group of 3 windows occupying the whole screen (except the menu bar, of course).

If you would like to let Apple know…

http://www.apple.com/feedback/macosx.html

I for one don't even use split view much less "triple" view.

FWIW, there is a third-party app called "Divvy" which may suit your needs.

I haven't found a way to have 3 apps side-by-side, but with the new 21:9 aspect ratios, WQHD resolution, 3440x1440 pixels or higher, it would make sense to support 3 apps. It's like having 3 seamless displays in one, at a possibly cheaper price. Apple should support this feature, it's kinda strange not to.

You can do this manually but not via the auto split view.

I love Divvy but I so wished I could do so as a Full Screen group!

I've submitted the feedback, thank you. Divvy looks like a desktop layout tool, but not a virtual desktop tool. I can put 3 apps side-by-side on the desktop, but not on the other virtual desktops (i.e. spaces). The Divvy description doesn't suggest it would do that. Thank you.

2 apps is the limit for split screen view.

You're welcome.

any luck with apple?