Posted over 6 years ago. Visible to the public.

Many box shadows will make your app unusable on smartphones and tablets

Box shadows are awesome. Unfortunately they are also very costly to render. You will rarely notice the rendering time on a laptop or desktop PC, box shadows can make your app completely unusable on smartphones and tables. By "unusable" I mean "device freezes for 10 seconds after an user action".

But isn't it the future?

Not yet. Eventually mobile devices will become powerful enough to make this a non-issue. However, currently (August 2013) even high-end smartphones can become very unresponsive with a box-shadow heavy application.


A quick workaround is to simply not render box shadows on mobile devices. To do so, use our touch device detection card to apply a touch_device class to the document <body>. Now you can add a rule to your CSS/Sass:

body.touch_device * -moz-box-shadow: none !important -webkit-box-shadow: none !important box-shadow: none !important

Also see

Growing Rails Applications in Practice
Check out our new e-book:
Learn to structure large Ruby on Rails codebases with the tools you already know and love.

Owner of this card:

Henning Koch
Last edit:
over 3 years ago
by Henning Koch
About this deck:
We are makandra and do test-driven, agile Ruby on Rails software development.
License for source code
Posted by Henning Koch to makandra dev
This website uses cookies to improve usability and analyze traffic.
Accept or learn more