Here are a few quick ideas:
1. Build customer loyalty. Everyone likes to feel included in something special, so make customers feel like VIPs by offering discounts, coupons, and promotions just for using the app.
2. Create viral buzz. Encourage customers to use the mobile app to quickly tell all of their friends about the business using the built-in sharing capabilities of Facebook, Twitter, LinkedIn, your blog, SMS, and Email.
3. Grow customer lists. A mobile app can gather names and email addresses from directly within the app and easily export them into the top email marketing campaign services to be used in additional emails.
4. Get instant feedback. Mobile apps allow customers to leave feedback on fan walls, share photos, make restaurant reservations, and send comments in a variety of ways.