How To Go Viral Faster

Growth suggestions for Nextdoor

Debra Teo
Debra Teo
May 23, 2016 · 6 min read

The secret sauce of reducing viral cycle time is an often over-looked component when optimizing for viral growth. In fact, reducing viral cycle time has the greatest effect on the viral growth of your product.

Recently, I adopted a cat named Apollo from my neighbor through Nextdoor, a social network for neighborhoods. It took about 3 weeks from the initial sign up to performing an action (responding to a cat adoption posting), and then finally recommending Nextdoor to my friends and co-workers by word-of-mouth, “I adopted a cat from my neighbor through Nextdoor!”

That 3 week period was the time it took for me to complete the viral cycle.

My hypothesis is that if we can find ways to reduce this gap from 3 weeks to a shorter period, the viral growth for Nextdoor will dramatically increase.

What Is Viral Cycle Time?

The viral cycle time of your product begins the moment users see and decide to use your product. Users then interact with your product, and upon deciding that they like it enough, invite their friends. The friends who receive the invitations will then decide to take a look at the product, and the cycle starts over again. Viral cycle time is the time it takes for one such cycle to complete.

In other words, viral cycle time is the amount of time it take for a user to invite another user. The faster a user completes this cycle, the shorter the viral cycle time of your product.

“[If during every cycle a user invites two additional users] After 20 days with a cycle time of two days, you will have 20,470 users. But if you halved that cycle time to one day, you would have over 20 million users!”

— David Skok, General Partner, Matrix Partners

Every Founder’s Dream

If you’re a founder or growth marketer, it is your dream for your product to ‘go viral’. You want to see your users’ friends and family share the product and invite one another to use it. This leads to more users, engagement, brand popularity and ultimately, the growth of your business.

A product’s viral coefficient (K) can be measured as the number of invites multiplied by conversion rate. The holy grail in viral marketing is for (K) to be greater than 1 to achieve dramatic viral growth.

t = number of cycles or generations

Custs(t) = number of users at generation t

Growth Strategies for Nextdoor

I love Nextdoor. It is a free, private, social network that enables members to communicate with their neighborhood community.

It already has referral programs in place that contribute to increasing its K factor:

1. As a user goes through the sign up flow, they are prompted to invite his or her partner.

2. When a user enters the home screen, an “Invite” button permanently appears in the top left of the screen.

This is what Nextdoor’s current viral flow looks like:

Ways to shorten viral cycle time

1. Delighted users share

I was a delighted user the day I brought Apollo home. I opened the Nextdoor app’s built-in messenger to let Elizabeth, Apollo’s original owner, know that Apollo was getting settled in. She replied and told me how thankful she was for him to have a new home.

At this point, I instinctively wanted to share this with my family and friends outside of Nextdoor. Unfortunately, there wasn’t a way for me to do so via the app. The invite button was not a feature I would use to share about how awesome the product was. I wanted to share about my experience, not necessarily invite someone to the app.

This is a lost opportunity to shorten the company’s viral cycle time. Remember, that’s time is the amount of time it takes for one user to invite another user.

Delighted users would want to share with their family and friends. What we want to do is to provide an avenue for these users to share quickly, intuitively, and through their sharing, invite additional users.

A solution would be to bake in a “Share” function, whereby users are prompted to Share whenever something good happens to them. The moment they share, it becomes an opportunity for someone to see it and sign up for the app.

2. Don’t make them wander

Currently, once users get past the sign up flow, they are brought to the home screen, an “All Activity” feed. Users get to see what is going on in the neighborhood based on what their neighbors are posting.

This works for the casual explorers who may want to get a sense of what their neighbors are talking about, or what the Nextdoor app is at a glance.

However, this is also a huge avenue where users can wander around the app, and eventually drop off when they can’t find anything beneficial to them. It’s likely that allowing this kind of exploration is actually lengthening the cycle time.

This can be avoided by adding constraints. One way to do so is to provide a more structured onboarding flow might encourage users to provide information about their preferences and then use that to generate a personalised home feed.

3. What They See Is What They Want

When users get to provide information about their preferences, the app gets to learn about the users’ expectations. This will increase the chances of the app delivering delight quickly.

In the following example, the user is interested to know who else is on the app and also where he or she can get groceries. When the user selects “My Neighbors” and “Groceries” as part of the onboarding flow, Nextdoor is able to use that to generate a relevant feed.

Now, when the user lands on the home screen, he or she immediately sees a few familiar faces because Nextdoor surfaces nearby neighbors ranked in order of proximity to his address.

These familiar faces helps to build trust and credibility. This user also finds savings and promotional deals from nearby local grocery stores.

What We’ve Learnt

To shorten viral cycle time, these are 2 principles that can be applied to every viral loop:

● Allow for quick discovery. Don’t make users wander. Once they land on your app or website, guide them to find their utility or perform a desired action.

● Once users perform a desired action, don’t stop there. Give them opportunities to share. Delighted users share, so make it easy for them to do so.

Not About A Single Tactic

At the end of the day, a viral growth strategy is never about a single tactic. If a user can be guided to reach his or her personal promised land quickly and then share it on social platforms to their friends, the time it takes to get from sign up to inviting new users will be greatly reduced.

Often, viral growth strategies are thought up as an after-thought. These strategies are usually focused exclusively on the K factor. However, when growth strategies are baked in early on, as part of product and design decisions to shorten cycle time, user growth will increase drastically.

If you’re interested in working with me or just want to say hi, drop me an email at and follow me on Twitter.

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Debra Teo

Written by

Debra Teo

I write about Growth, Marketing and Content Strategy. Currently Growth Marketer @ Aiooki


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