Unlike e-mails, where sometimes sending a daily e-mail is OK, it is not OK with mobile marketing. Craft some content where you are sending 2-4 messages/month to start with. At least 50% of your messages should be NON-promotional. Keep the audience engaged. Don’t just spam them with offers. Thank them for their business; send birthday messages, happy holiday messages, contests, and member-only specials just to name a few.

Article source: http://www.huffingtonpost.com/entry/mobile-marketing-101_us_59070e29e4b084f59b49fac3