Not that it's a real solution, but you can run Safari and Chrome side by side.

I think the real solution is for Safari, and apps like it, to allow side-by-side viewing of tabs on devices that have a "large enough" display.

There's no reason this needs to be an OS feature, and at least one good reason why it shouldn't be: data integrity. Threading is hard enough for most programmers to get right, and now you want to require IPC and/or coordinated access to every apps' data files?

I love that this is already being provided by an enterprising app developer, but I hope they get Sherlocked.

There is an app Split Web Browser that does this. (Maybe others)