For those that are looking to save time, have a look at the https://wrapbootstrap.com/
There are a lot of fantastic pre-built themes that you can use to style your app. I personally am using it for Ideas :)
They are not free, but cost between 10 and 20 USD.
Of course, there are a zillion free plugins too of course.
Here's one site that I really like for freebies.
http://www.jqueryscript.net/
I'll post some demo's of the ones that I am using.
Herb