Fiori app development is split in two places. Gateway, and SAPUI5.
The SAPUI5 development should be done in Eclipse, with the latest plugins. A long time ago when we developed HTML5 apps based on Twitter Bootstrap, jQuery Mobile, Sencha Touch, and other HTML5 frameworks, we would manually upload and download all the files into a BSP. Now, there are several ways we can streamline the process.
Download the latest Eclipse, at this time 4.4 Luna: https://tools.hana.ondemand.com/luna/
Click on the Eclipse downloads link, then choose the first option Eclipse IDE for Java Developers (64-bit was my choice). This will be a zip file. Simply extract this to the folder of your choice, then inside this folder, click on the eclipse executable, and it will launch and you can select your workspace area.
Go to Help->Install software and insert the URL: https://tools.hana.ondemand.com/luna/
Select all the components, and click install.
You can see the sapui library is 1.24.2