I've gotten a lot of questions from people about how folks use emoji/emoticons in Grindr, so I thought I'd give a little how-to session.
First off, emoji is a system-wide option, not something specific to Grindr, so once you unlock them, you can use them in all apps that support them, including iPhone-to-iPhone messaging, emails, etc. Emoji is hidden within the Japanese language options and is locked with the standard English-based iPhone OS. The goal is to unlock the emoji option and release the emoticons to an unsuspecting Grindr world.
To begin, you'll need to download a free app from the App Store called Spell Number. Just so you're not confused, this app has nothing to do with emoji. What it has is an Easter egg that will allow you to unlock the emoji with a few easy steps.
Once downloaded, launch Spell Number and type in the number 91929394.59. Now close the app by pressing the Home button. Open "Settings". Go to General --> Keyboard --> International Keyboards --> Japanese, then turn "Emoji" to the On position.
You'll know you're successful because your keyboard will change slightly. A globe now will appear between the "123" button and the spacebar. Touch that new globe button to access emoji in any app that utilizes the keyboard.
And that's it! You've unlocked emoji!