Millennials are obsessed home screen decor.

In fact, more than 1 in 5 (21%) have deleted an app in the past year because they didn’t like how it looked on their phone or tablet’s home screen, according to comScore’s annual mobile app report.  That was almost nonexistent with Gen X users (just 2%) Baby Boomers (3%).

“You look at that screen every day, and you see these brands staring back at you, so there is no doubt that it confers social identity,” Andrew Lipsman from comScore told Moneyish. “Millennials really think of their phones as status symbols. And what apps you see on your screen – the combination of colors, the brands and what they stand for, say a lot about you as a person.”

Lipsman, who admitted he’s on the tail-end of the Millennial spectrum, said his home screen is all news apps, for example. “I’ve got the New York Times and the Wall Street Journal, email and Twitter, which aren’t very colorful, which says I’m a geeky news reader,” he laughed. “The more colorful ones like Snapchat, YouTube and Buzzfeed are on the next screen. I’m all business on the home screen, fun on the second screen.”

So what makes an app logo cool enough to park itself on someone’s primary screen, where comScore found users of all ages put their “most essential” apps?

Scott Lewis, a designer and curator of Iconfinder.com’s collection of app icons, and app logo designer Michael Flarup told Moneyish a few general rules of thumb to crafting a sexy app that everyone wants to tap.

First, keep it simple. Can the logo stand up to being scaled down phone screens – and made even smaller if it’s sorted into a folder? If it’s got too many colors, or tries using 3D block letters, those details can easily be lost. “I personally like to make logos that make great stickers and that people would want to put on their laptops,” Flarup suggested, like 1Password, whose black keyhole in a high-tech gray and blue color palette still resembles the number one when it’s scaled down – getting the point across at every size.

And it needs to identify your brand or what your brand does. A lot of users hated the redesigned Uber app, which nixed the recognizable “U” for what looks like a backwards “C,” or something.

“Especially when you may have dozens of apps on your phone, being able to locate the app that you want quickly is going to be important,” said Lewis. Package tracker app Deliveries shows familiar brown packaging with a white label and barcode, for example.

And does it stand out from the rest of the pack? Note how many “productivity” apps use the same checkmark, pen or calendar page. And who hasn’t been annoyed by opening the wrong app because they all look the same, such as how your iCloud Drive icon looks just like the Weather app?

“Fun and personable always wins,” said Flarup, praising Snapchat for managing to “defy the rest with its quirky ghost character and bright yellow.

“I think utility icons can learn a lot from (video) game icons, which often do a much better job of pulling in the viewer and conveying emotion,” he added, highlighting how Tweetbot reinterprets the iconic Twitter bluebird as a cute robot.

Flarup also suggests avoiding just a lazy single letter or word. “You’d be surprised by how many people smack a simple glyph on a single color background and call it a day,” said Flarup. “Very popular apps with brands that are known throughout the world can get away with this, however, this is more often the exception than the rule. Not everyone is Facebook or Google.”

App designers should take those words to heart, since Millennials are serious about the layout of their home screens. The comScore report also found Millennials are more likely than other age groups to curate their apps, such as filing their utility apps (calculator, calendar, etc.) into a folder.

“There’s a strong correlation between how essential an app is to a user and whether it gets placed on their home screen,” the report also noted. So apps that were ranked “most essential” – and in Millennials’ case, that was Amazon, Gmail and Facebook, in that order – were set on the primary home screen where their thumbs could easily reach them – since younger users are also more likely to use their phones one-handed.