I currently responsible in building e-form in Nintex Forms and Workflow using the SharePoint Foundation 2013. Our solution is On-premises version. We are looking to go also for mobile form.
do you have a partner you can discuss this with?
nintex app studio allows you to design and package up mobile apps for each solution where you have complete control on branding etc.
nintex mobile allows you to push out mobile layouts to the nintex mobile app which is nintex branded and rolls all content for user into one app.