Future and DJ Khaled emojis.

Future and DJ Khaled emojis.

Courtesy of Moji

What's the value in an emoji? That depends on who you ask.

The use of emojis -- illustrations used as texting shorthand for almost any word or emotion -- has exploded in the past 18 months, with an estimated six billion icons sent worldwide each day, according to a 2015 study. DJs, rappers and bands quickly picked up on the trend, turning personal quirks and tendencies into distinctive branded packs with dozens of images, such as a one-eyed smiley face for Fetty Wap, or a smattering of Future's now-famous hat collection.

And the emoji craze is still growing; a March 2016 study conducted by digital marketing company Appboy found emoji use in messages has increased eightfold since last year, with growth in 2016 alone rising by 20 percent month-over-month.

Courtesy of Moji

Unsurprisingly, entrepreneurs have taken notice, and digital stores such as Moji Keyboard, Emoji Fame and Imoji are creating emoji packs for artists and celebrities -- a trend that has picked up since Kim Kardashian's Kimoji set shot to the top of iTunes' Top Paid Apps chart a day after its December 2015 release. "We look at it as the new hashtag," says Moji founder/CEO Oliver Camilo, whose company created emoji packs for over 20 artists such as Wiz Khalifa, DJ Snake, G-Eazy and most recently Rick Ross, as well as standalone emoji apps for Amber Rose and Kevin Gates. (Moji is also about to delve into the sports world, with a new Steph Curry pack due out tomorrow, May 26.) "Just like everyone needs to have their own Instagram or Snapchat or Facebook page, eventually everyone is going to need their own emoji."

There are plenty of reasons for artists to get in on the trend. Both Moji Keyboard and Emoji Fame are free apps that operate as standalone emoji stores, offering artist-specific downloads within the app for $0.99-$1.99 (or even free) depending on the artist's wishes. Revenue sharing with the artist generally hovers around 50 percent, depending on the contract, with deals usually taking the form of image rights contracts. And though in-app purchase numbers aren't available, demand has sent both Moji Keyboards' standalone apps to No. 1 on iTunes' Top Paid Apps chart upon release, while mobile analytics company Flurry found in January that emoji keyboards were the main driving factor behind the 332 percent increase of "personalization" app sessions in 2015.

Zakk Wylde

Zakk WyldeCourtesy of Emoji Fame

With that kind of engagement, direct revenue from emoji pack downloads can take a backseat to their value as a marketing tool. Emoji Fame, which has created packs for rappers like Hopsin and Dizzy Wright and just debuted a collaboration with Black Label Society frontman Zakk Wylde, allows artists to send push notifications to users who purchased their packs, creating a line of communication directly to fans' phones.

"We can roll out new emojis on the fly in conjunction with tour dates, album releases, single releases, or even if an artist wants to jump on a meme," says Emoji Fame co-founder Gavin Rhodes, who runs the company with co-founder Michelle McDevitt; the two are also co-founders of publicity company Audible Treats. "It's a really important new frontier in terms of artist engagement on a very personal level."

It's also a useful way for artists to reach fan bases that are increasingly flocking to closed messenger tools like WhatsApp, which was purchased by Facebook for $19 billion in 2014 and passed one billion users in February, and the separate Facebook Messenger, which claimed 900 million monthly users on its own in April. "From a monetization perspective you can sell this product, and it's also a highly-effective marketing tool," says Camilo, whose company will soon roll out more advanced analytics tools to better show artists and their teams who is buying their emoji packs, and from where. "It's very unobtrusive, and users kind of evangelize the product for us as they text it to their friends."

Stephen Curry

Stephen CurryCourtesy of Moji

Still, revenue and marketing aside, many artists see emojis as just another way to give back to those who have supported them. "For me with Black Label, we don't have fans, we have fam, [and] it's just a great way to keep in touch," says Wylde, whose emoji pack is available for $1.99 and has sat atop Emoji Fame’s in-app purchase list since its release May 18. "If we can pay for a couple things [with these], that would be wonderful. But we're just having a good time."