E-commerce Link: Highly Responsive
There are a number of other factors besides navigation and content that need to be taken into account, as well: including technology limitations, visual design and layout, and project management and staffing.
With all of these things to consider, creating a responsive site only makes sense if you are already developing a new site or planning on overhauling an existing one.
When to Create a Mobile Website
In contrast, a mobile website should be built instead of a responsive site only if the desktop site is not going to be redesigned.
Strong user research, reliable analytics reporting and interpretation of data are required to know when a mobile site is needed. This information will identify what parts of your website users are looking for the most and how frequently they are visiting your website with their mobile devices. If you have determined a mobile site is needed, you can develop one designed specifically for mobile users.
However, if you are creating a new site or doing a major redesign, a responsive site is a better option. With careful planning, a responsive site can and should be a well-designed experience that addresses users' needs based on the size of the browser window. The Children's Museum of Pittsburgh website (pittsburghkids.org) is a great example of this.
When to Build an App
Apps should only be created if the built-in features of the mobile device are needed.
The biggest difference between an app and a website, responsive or mobile, is the ability of an application to utilize the features of a phone to perform a task. Probably the most publicized case of this was with the release of the iPhone 5, which highlighted the fact that only an app can provide spoken turn-by-turn directions. Another example of leveraging a phone's features are banking apps that allow users to make deposits by taking a photo of a check using the camera.