App creation is such a simple process in Papertrell. If you already have a Epub version of book available, you can straight away follow the below mentioned steps.

1. Log in to your account in Papertrell (

2. In Dashboard , Click  "Add new title".

3. Select "Import Epub" tab > choose and add the single epub file /multiple epub files based on requirement>choose any template "Blank Templates/Sample Templates/ My Templates"  and click Import.

4. Storyboard page shown.

4. Click "Preview on Device" button.

Wohooo. App is created. Next step for you is to view the app in your device . 

Refer to "How to Preview your app in device"