Notification System Design (99+)
This is a post about the different challenges that come along with working on notification systems from a product perspective. I’m going to overload the term “notifications” in this post, but what I mean is: in-product notifications, push notifications, email, and system generated text messages. My experience in this space has been from spending some time working on Quora’s notifications, Quora’s feed, and Email (Gmail / Inbox). I’ve been wanting to write this post for a long time (almost two years actually) because I think notification systems are a unique and interesting problem space that most designers don’t get a chance to work on, especially at scale. In addition, I think notifications are an incredibly powerful tool for a product person to wield that often get underused or abused to maximize short term gains.
What are notifications good at?
Before I go into what makes it challenging to work on notifications, I want to make it clear why they are worth working on in the first place. A notification is the product communicating with you while you are not using it. It is a naturally interruptive and invasive experience to various degrees. Because of that it is a very consequential system, meaning that every thing you send through it will have material impact on the user’s experience with your product. Compared to something like a feed where the user is in greater control over when they read it, how fast they scroll through it, what they do with each item in the feed, etc. So given that, notifications are effective at these things:
Engagement: I cannot overstate how effective notifications are at getting someone to use your product. Every notification regardless of the intended purpose will likely lead to more engagement, but there are many examples of notifications with the explicit goal of pulling you back to the product. These are essentially advertisements. For example, any digest email. One common property of a notification that has an explicit engagement goal is that they don’t need to be sent, meaning that the user doesn’t necessarily have any expectation that they will come. This is what makes them powerful and dangerous. Most people have experienced some abuse of this by some app who has wielded this for some sort of short term gain. “Happy Valentine’s day, we love you, come check out our app today!”