The last few months have seen a surge in the use of customers visiting online stores from their handheld devices. To better support these customers the Back In Stock registration form will scale to fit the screen width on a narrower devices, such as smartphones or small tablets. As long as you are running the latest version of the app on your site you don’t need to do anything to enable this feature. If you’re not, you’ll see an upgrade button on the ‘widget settings’ page which will update your site automatically with one click.
There are a huge range of devices on the market now and this is only going to grow in the future. I want Back In Stock to work well on as many as possible, so if you notice any rendering issues on a certain device please let me know by dropping an email to firstname.lastname@example.org.