you know if it´s posible put a index.html file as default page of a Sharepoint hosted app instead a Default.aspx page?
Thanks in advance
Assuming you are using Visual Studio 2017, right click on the Pages folder in the solution and select "Add" and then "New item". Choose to add an HTML file and pick any name, such as "index.html". Next, open the AppManifest.xml file. On the General tab, there is a field named "Start page". Set this to the HTML page you just created.
While supported, using an HTML file means you are responsible for bringing in the SharePoint chrome and other SharePoint web styles that you may want. Some of that is wired up already in the Default.aspx page.