When you click some special icons, you will transport to a new secret level! So watch out!

Icon	How to unlock
Agent P (The platypus/agent Perry at the Phineas and Ferb show)	In the mode selection, slide the page to very bottom and then click the blue duck.
Good Morning	In the collecion menu at "SWAMPY" mode, slide your left finger until the top of the page and hold it! Keep sliding the page until you found a sun icon.
Mi Amore	In the achievement menu at "SWAMPY" mode, slide your left finger until very bottom of the page and hold it! Click the heart icon.
Mining Laser	In the challange menu at "CRANKY" mode, slide your left finger to the top of the page, HOLD! Click the skull icon.
Mysterious Planet	In the episode selection at "MYSTERY DUCK" mode, click the planet icon.
Planetarium (Similiar like Mysterious planet, but it more harder)	In the achievement menu at "SWAMPY" mode, slide your left finger until very top of the page and hold it! Click the planet icon.
Sara's Level	In the food group menu at "CRANKY" mode, slide your left finger until very top of the page, hold it! Click the atomic icon.
Undergroud Adventure	In the collecion menu at "SWAMPY" mode, slide your left finger until the very bottom of the page and hold it! Click the spray icon.
Ups and Downs	In the collecion menu at "SWAMPY" mode, slide your left finger until the top of the page and hold it! Click the 2 up and down icon.