I have a product designed for mobile browsers.
When I promote the site to my target audience, I find that they understand the term "app", but terms like "website" or "web application" do not generate the same level of understanding.
I don’t like saying “app” because it misleads users into thinking they can find my product on Google Play or Apple iTunes. I have a long-term goal to get my product in these stores, but, in the meantime, I need to make potential users understand what it is.
My target audience are mainly people I talk to face-to-face; although some of my users have signed up simply through word-of-mouth.
How do I effectively communicate my mobile site to non-technical users?
We use 'web app' a lot and I don't really find that people struggle to understand what we are referring to. Particularly, if we are meeting face-t-face. More recently, we've been using the term 'Responsive Design' to communicate that our web apps render correctly no matter which device the site is accessed from.
Perhaps you shouldn't define your site in terms like "app", "website", "site", "mobile web", "Saas", or "web app".
Perhaps you should just think of the benefit your site gives to mobile users and use it.
e.g.
"Go to mint.com from your mobile device to manage your money"
Lots of money / time has been spent to "educate" consumers about mobile phones and apps. Think about how many people equated AOL to Internet.
I would focus on what value your service provides - and promote that it supports optimized experiences for mobile, tablet and desktop users. No dedicated app necessary. (No searching in app stores/ authorizing installation / creating duplicate accounts).
You could go the extra mile and show visitors how to create a shortcut on their device.
Try to make the definition of your service short & sweet, ideally no more that 70 characters if you can. This will help out your SEO in the future - especially if most of your marketing is direct face-to-face, you want the users to be able to find your website easily.
If your site is targeted to non-technical users then having tutorials on how to use the site must be prominent and easily accesible for users.