I believe responsive web design is good because it solves the mobile friendly website challenge in the least amount of time/cost.
- One stylesheet for all devices
- Can be setup by one designer/developer
- Easy to maintain and update
- Less expensive – Does not require server side device detection or complicated mobile app programming
- Does not require mobile app marketing to educate people to download your app : (
- If you want to share a link to your site you share your domain name. Sharing apps is not that easy.
Cons
- Hard to test across all devices and breakpoints
- If not done properly, can cause mobile sites to load slowly due to high resolution images for desktops
- If you are an older developer going from desktop first to mobile first it can be a learning curve to learn the new workflow
- Hard for content authors to write text mobile-first. So you often have to display a page of text on an itty mobile device : (
