I’m doing my first conversion of an existing website to a responsive site. The client wants the basic theme to stay the same, just make the elements responsive – that is, fit them according to the device. So far it is going pretty well, except for the exceptional use of <div> tags by the original designer plus a table here or there where the designer couldn’t figure out how to float elements.
One drawback is that when testing the site on my smartphone, it caches the page so I can’t immediately see changes. This was frustrating. I used an online Opera emulator, which helped but, as always, the devil is in the details. The main thing I’ve learned is don’t try and float elements in the smaller screen sizes. Just stack them one over the other.