How do you measure an app’s success? The common answer would be in the number of downloads or the average star count in the ratings. Emoji—one of my favorite iPhone apps—was in part responsible for my choice to up the number of texts in my iPhone plan. That’s a tremendous success metric for AT&T, anyway.

In case you’re not familiar with this Japanese application, it is a keyboard-accessible library of emoticons, smileys and other fun icons that spice up mobile messages, notes and emails. One downfall, however, is that it only works with other iPhones (thus augmenting the unfortunate “members only” mystique). In fact, depending on which non-iPhone you’re sending a text to, the message may vanish entirely…making it the mobile equivalent to lost laundry socks. The app still has upwards of ten thousand five-star ratings. Despite resistance earlier this year, Apple is now offering some help on troubleshooting with Emoji.

Last month, my colleague Stephen Koch told me about a game he and a few of his friends play where they use Emoji to illustrate band names. The recipient of the message has to decode them.

I hopped aboard. Since it’s Friday, I thought I’d share a handful with you. Some are caveman-level easy, others are a bit obscure. Feel free to submit your response in comments (I’ll wait a few days before posting any answers).

G’luck.