Here are the steps you can use to opt out of Osmo app cross-promotions:
1) Go to my.playosmo.com. 2) Click on the 'Account' link on the left. 3) Click on the 'Games' link on the left. 4) Scroll down to the 'Recommendations' section of the page. 5) Check 'Disable Recommended Games' to turn off promotions.