I don't think those are the official shields. I didn't put much effort into finding the right ones.
EDIT: Here are some other unofficial ones. I don't think there are any official shields for JS or CSS:
http://js.devexpress.com/Content/Images/features/html5-css-javascript-logos.png http://www.geekchamp.com/upload/tutorials/html5_css_javascript.png http://www.photolibrarysoftware.com/wp-content/uploads/2015/11/html5-defeats-adobe-flash.jpg
IMO storage is the simple part. It's really just need a table with standard properties for the event like start, end, asset info, completed, etc. Then you let the components handle the ui, conflicts, time segments, etc.
I can't remember if they have the capability to directly handle the database (I want to say that they do if you don't need to customize anything, but it's been a couple of years since I last wrote anything in it). I used their scheduling / calendar controls to write an employee scheduling system, and used my own POCOs to represent the objects behind the schedule.
They have very good samples that you can download and run through to see how they are put together.
For me the pricing is pretty reasonable for what you get, but I use a lot of their controls (reporting, UI, grids, scheduling, etc), and writing even one of those would take more time than I have available all year.
That said, I haven't actually worked with the JS / HTML5 variant (http://js.devexpress.com/WebDevelopment/MultiPurpose/). I've mostly done desktop work with the Winforms and WPF variants.
We certainly use standalone .js files without Phonegap application, although we don't use their cloud service to build/package the application.
I use Phonegap in conjunction with the DevExpress DevExtreme mobile framework which has its own methods for packaging.
[Edit]
Yes, it does:
>What Do I Upload?
>Preparing the Assets
>PhoneGap Build only requires the assets of your application. This is essentially your www directory which contains your html, css, images, js files, etc.
I prefer stacked area charts showing percentage of total. Pie charts don't show trends over time.
Pie charts can be extremely useful if you're trying to push a particular agenda, or a changing variable, such as time, is not required.