It trolls Donald Trump in the crudest way possible.
If you could predict the 2016 presidential election by each candidate’s smartphone apps, Donald Trump would win by a landslide: There are 171 mobile apps relating to the Republican frontrunner, more than twice the amount for each of his Democratic contenders Hillary Clinton and Bernie Sanders, according to new research by Sensor Tower. Among the other GOP candidates, Ted Cruz has only 25 apps created in his honor, while John Kasich has just two.
But the 1.8 million people who have downloaded the most popular Donald Trump app, called “Trump Dump,” probably aren’t going to vote for him: The app is a game where the prize for winning is getting to drop a deuce on the The Donald.
The game itself is pretty simple: You deftly try to guide a bird through a gap in a brick wall that is fast approaching, tapping the bird to make it fly higher (in a way similar to the famous “Flappy Bird” gaming app). If the bird clears the wall without smashing into it, you get to make it take a virtual crap on the candidate—releasing more droppings, in the form of poop emoticons, each time as you advance to the next level of the game. As the bird relieves itself, the Trump emoji morphs into a large pile of poop wearing a Trump-like toupee and matching golden eyebrows.
Since the Trump Dump app launched January 25, it quickly went viral, climbing as high as the No. 2 free app in the Apple aapl app store rankings. Its growth this year has eclipsed that of more mainstream apps: In that timeframe, Trump Dump was downloaded more times than the apps of Starbucks sbux , Lyft, Foursquare, and mobile payment company Venmo, according to Sensor Tower, which tracks app downloads and popularity.
Not only is Trump Dump by far the most popular app relating to Donald Trump—who does not have an official campaign app—it’s also the most popular election app, period. None of the other 170 apps dedicated to the “Make America Great Again” politician—or at least dedicated to trolling him—have managed to crack 100,000 downloads. And Trump Dump has also been downloaded more times than the top apps of the other four candidates (listed below)—combined. Even the Fox News election app has only been downloaded about 525,000 times.
Created by a pair of 19-year-old twin brothers from Maple Grove, Minn., college sophomores Jason Fotso (Duke University) and Brian Fotso (Baylor University), Trump Dump was the first app they ever developed, inspired by a “daydream,” which is what they named their company. They are not affiliated with any other candidates’ campaigns or Super PACs—nor do they support Trump, in case that wasn’t obvious: “‘Trump’ and ‘Dump’ are rhymes. And synonyms,” the Fotsos explained in an email to Fortune.
The Trump Dump game also comes with a disclaimer: “For humor purposes only. Not to be taken seriously.” It goes on to say that “reference to any celebrity” or other person “does not constitute or imply sponsorship, endorsement, or recommendation.” As for the developers’ own political leanings, they tell Fortune, “As brothers ourselves, we admire the legacy of brothers John and Robert Kennedy for their commitment to cultivating an America that embraced a young generation, stood for civil rights, and worked towards equal opportunity.”
Here are the most popular apps for each of the five presidential candidates, ranked by number of downloads as measured by Sensor Tower:
- Trump Dump (1.8 million):
“It’s simple: Beat the wall, dump on Trump,” the app’s instructions say.
- Bernie Sandwiches (111,000):
Feed deli subs to Bernie Sanders in this game because “Bernie can’t make it to the White House on an empty stomach!” according to the app’s description. While the app’s disclaimer says it is not affiliated with or endorsed by the Bernie Sanders camp, it does promise to donate a portion of the game’s proceeds from ads to Sanders’ campaign: “So if you’re a Donald Trump supporter, but secretly love this game, you might be helping Senator Sanders :-).”
- Ted Cruz 2016 (68,400):
The official Ted Cruz election app, funded by his campaign, allows users to earn points and win Cruz gear by checking in at the Republican caucuses, canvassing for the candidate and other supportive activities.
- Avoid Hillary (3,000):
Billed as a “political satire arcade game,” the app also “raises important topics for discussion,” according to its iTunes description. Players are instructed to “Do your best by being elusive and hard to pin down as you Avoid Hillary.”
- John Kasich 2016 (2,700):
The official Kasich campaign app lets users sign up to volunteer, contact the campaign—and of course, donate. The seven people who reviewed the app’s current version gave it a five-star rating.