Firstly you can get 10 additional recipes by applying a "referral code" from another Eatly user. If you don't know anyone else with Eatly, ask someone else to download it and get them to tell you their referral code.
The other way is by sharing Eatly with other people!
To share a recipe (with your referral code included) simply click the icon in top right hand corner of a recipe.
To share the app itself (and to see your referral code) use special share button at the bottom of Eatly's main home page.