If you own a smartphone, you definitely know what push notifications are. They're those pop-up alerts on your lock screen that you get depending on which apps you have push notifications set up for.

Some are more informative than others. For instance, if you have CNN's app loaded on your phone, you'll receive notifications any time there's breaking news. If you've signed up to receive special offers from Red Lobster, it'll send you a notification letting you know when its Endless Shrimp specials are going on. Have an app for RetailMeNot? Be on the lookout for some awesome savings.

Push notifications are the perfect calls-to-action (CTA) that grab the attention of your audience whether they're currently looking at their phone, or playing catch-up when they finally get around to scrolling through their alerts.

But have you ever thought about what goes in to writing the best push notification copy? The content has to be original, fresh, and compelling. Here are some ways to ensure you receive the greatest amount of opens and conversions on your push notifications.