I am new to SharePoint and Exploring the Office 365 Small business feature online using trial subscription.
I'm able to create 'App Parts' using Office 365 Developer Site Subscription(by using 'NAPA' SharePoint Developer tool).
Now I wanted to create SharePoint 'Custom WebPart' in Office 365 online without using Visual Studio 2010,2012,2013.
Please Guide me on this by providing some reference links for creating "Custom WebParts" in Office 365 Online and how can i use created web parts.
Edited:
Are there any online tools or sharepoint apps like 'NAPA' available for develop custom Web Parts online?