We found out which apps and filters the stars use to help them look skinnier and hotter in their selfies.
According to Zoe Saldana, "the key to a good selfie are the filters."
"Once you tweak it, you can make it look amazing," said the Guardians of the Galaxy star.
The Instagram filter Sutro can actually make you look thinner, because it has burned edges and increases shadow. Hubspot.com's Dan Zarrella filled us in on some other miracle-working filters.
"When [Taylor Swift] uses Mayfair, which is one of my favorite filters for selfies, she actually gets 49 percent more likes than her average Instagram photo does," said Dan. "It's warm. It'll bring out little highlights and contours in it."
Watch the video for more.