Where do I use the blue shell?

That blue seashell is a limited item from the Playio Festival. Its expiration date is today, so hurry and check the event page for where to use it. It would be a real shame to forget and have it disappear, wouldn't it?

You mean the event page? You can access it from the horizontally sliding banner at the very bottom of the Today tab.

Hmm, nope. Don't have it... Maybe it's because I'm on an Android tablet?

It's like this.