How can you be sure that theme you bought is responsive?
Everyday people use devices like mobile phones, tablets, pablets etc. Common feature of all of them are touch screens and smaller screen size. The intention of responsive design is to work on all devices.
When developing a theme, you must ensure that it will look good on, at least, 4 major devices: desktop computer, laptops, tablets and mobile phones. Which basically gives you the range from 27″ monitors (or bigger) to 4″ phones.
To have a responsive website, you need to use some responsive layout – one that adjusts according to the screen width.
The term responsive web design (RWD) was coined by Ethan Marcotte in May of 2010. He wrote an article where he described theory and practice of RWD principles. The rest is history. You cannot build web site today without it being responsive.
Test it out
When purchasing themes be sure to test the demo on all devices (if possible). This will ensure you that the theme is indeed responsive. You could also search for media queries in .css files (if you’re more tech savvy).
Lastly we’ll share article about responsive design, that we recommend you read: