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Mobile List Building 101: 8 Potent Opt-In Building Strategies

  • Conversion Rate Optimization

I probably don’t need to tell you that people love using their mobile devices these days. 

Many of us are glued to our phones, with the average person spending nearly three hours per day on them. 

But what really puts the mobile revolution into perspective is a few key data points, like “mobile accounts for approximately half of web traffic worldwide.”

Just check out this graph that shows how mobile web usage went from being 31.16 percent in early 2015 to 51.53 percent in 2020.

Also, smartphone usage has spiked in recent years, going from 2.5 billion users across the world to a projected 3.8 billion by 2021

Given that more people now access the web on a mobile device than they do on a desktop, it only makes sense that mobile list building should be a top priority. At the end of the day, you need your opt-in to be just as potent on mobile as it is on desktop. And that’s what I’m going to tackle in this post. 

Here are eight mobile list opt-in building strategies that will pull in mobile users like a moth to a flame and compel them to sign up.

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1. Use Large Fonts with Clear Contrast

Needless to say, mobile devices have a significantly smaller screen size than desktops. As of 2019, the majority of smartphones were 5–5.5 inches (12.7–13.97 cm), whereas the average desktop monitor screen was 22.1 inches (56.13 cm). 

Because mobile users are on such a small screen, using tiny fonts is going to make for an unpleasant experience, where they’ll struggle to see what your opt-in says. That’s why it’s important to use large fonts that mobile users can painlessly view when browsing your mobile site. 

There should also be adequate contrast, with either a dark font and a light background or a light font with a dark background. On top of that, there needs to be adequate negative space between copy and fields so that it doesn’t feel cluttered. 

This example from Pipcorn Heirloom Snacks, a company that sells healthy versions of classic salty snacks, does a great job at this. 

It’s also extremely simple and straightforward, which brings me to my next point. 

2. Use Short, Concise Copy

Like many other aspects of sales and marketing, I like to approach mobile list building with a minimalist mindset. Less is best in most cases, and this is certainly true when it comes to designing a mobile opt-in.

You’re dealing with very limited real estate, so it’s important to condense your copy and stick to the bare essentials. Take, for example, this mobile opt-in from outerwear and activewear brand Varley

It’s about as simple as it gets. There’s just a single sentence that tells shoppers to sign up to get 10 percent off (incentives are another strategy I’ll cover later on), followed by a field to enter their email and a straightforward CTA.

Yet, shoppers know what they need to do without exerting any major cognitive effort. The bottom line is that brevity is important with opt-ins in general, but it’s paramount for mobile list building. So always look to pare down your copy and ditch anything that’s extraneous. 

3. Use Minimal Fields

Generally speaking, the fewer number of fields you use for opt-ins, the higher the conversion rate will be. After all, “shorter forms generally require less work from users and logic suggests fewer form fields reduce friction,” writes Aaron Brooks of Venture Harbour

This data from MarketingExperiments proves it.

My point here is that fields aren’t your friends with mobile opt-ins, and the more hoops you make shoppers jump through, the less likely they are to sign up. 

And take a second to compare entering information on a mobile device as compared to a desktop. You have to use a touchscreen rather than a keyboard, which makes it more onerous and time-consuming. 

There’s also a greater likelihood of making an error, which means the person never even ends up receiving your content. So, you need to keep the number of fields to an absolute minimum. 

To quantify, I suggest using three fields max, which would ask for a person’s first name, last name, and email address. But if you can go lower and only ask for a person’s email address, like this example from modern essentials brand Everlane, that’s even better. 

4. Offer a Mouthwatering Incentive

“Seventy percent of subscribers open marketing emails in search of a discount or a special deal,” explains Ieva Baranova of Printful. “If your signup form promises this, your chances of attracting a new prospect are much higher.”

That’s why I often suggest offering some type of sweet incentive, with one of the most popular options being a discount, like the 35 percent off contemporary clothing brand Kensie offers.

I don’t know about you, but 35 percent off would definitely pique my interest, and no doubt is enough to persuade a sizable chunk of Kensie’s shoppers to sign up.  Another approach is to make a subscriber eligible to win a prize by opting in.

That’s just what women’s jeans brand Rainbow Shops does in this example. 

Here, subscribers can enter to win a $500 eGift card, which is definitely a sweet deal. The trick is to crunch the numbers and come up with an attractive incentive that will crank up your opt-ins without hurting your profitability.

5. Let Shoppers Know the Perks of Opting In

Another easy way to make signing up sound more attractive is to let subscribers know what’s in it for them. 

For instance, will they get the scoop on the hottest deals before anyone else does? Will they have early access to new products? Will you be sharing advice and insider tips? These are just some of the things that potential subscribers will be interested in. So, keep this in mind when crafting your mobile opt-in.

To give you some ideas on how to approach this, I’ve got two examples you can borrow from. First, there’s this one from coffee scrub brand Frank Body

They let potential subscribers know they’ll receive access to new products, tips, and more. 

Second, there’s this example from eyeglasses and sunglasses company Warby Parker, which tells shoppers they’ll be the first to know when new frames come out and when upcoming events will be happening.  

The key is to spend a bit of time analyzing the strengths of your newsletter and pinpoint what your brand brings to the table. Then, succinctly explain this in your mobile opt-in. 

6. Optimize Your CTA

CTAs sometimes seem like a footnote compared to other elements of a mobile opt-in, and as a result, are often overlooked. But as David Zheng of Crazy Egg points out, “as far as individual elements go, CTA buttons are among the most important.” 

A strong CTA button will inevitably lead to more conversions than a weak one. It’s that simple. So, this isn’t something you should overlook. 

On the contrary, I recommend putting plenty of time into, first, creating an awesome CTA, and then, performing rigorous A/B testing on it until you find a winner. 

When it comes to creating a CTA for a mobile opt-in, you don’t need to reinvent the wheel or get “too cute” because this can end up backfiring. But you should definitely follow some best practices, including:

  • Always using a button (not text or a hyperlink)
  • Using clear and concise language
  • Keeping it simple and straightforward
  • Letting shoppers know what will happen if they tap on the CTA

Here’s a great example from monthly beauty and grooming box subscription company Birchbox that checks all the boxes. 

7. Create a Personalized Experience

“Ninety-one percent of consumers say they are more likely to shop with brands that provide offers and recommendations that are relevant to them,” says Blake Morgan of Forbes. Further, “80 percent of consumers are more likely to make a purchase from a brand that provides personalized experiences.”

So, showing potential subscribers that you’re an e-commerce brand that’s committed to providing a personalized experience when mobile list building is a no-brainer. Not only does this increase the likelihood that they’ll sign up, but it also increases the chances that they’ll ultimately make a purchase, which is always the end goal.

But how exactly do you go about creating a personalized experience? One of the easiest strategies is to let subscribers choose what they’re most interested in. That’s what cosmetics brand ColourPop does with their mobile opt-in.

Subscribers can choose from three options—makeup, skincare, or body care. Then, ColourPop segments its list and sends ultra-targeted content that hits its mark. And notice that they do this without creating any complications or extra work for subscribers.

All subscribers have to do is tap on the interest that best suits them, enter their email address, and tap “Enter.” Boom! That’s it. So, I think this is an excellent way to make your opt-in more personalized and ensure that you get the right content to your subscribers. 

8. Use Popups Responsibly 

The debate about whether to use popups for opt-ins has been raging for years. Both sides have valid points, but the bottom line is that when used correctly, popups can dramatically boost conversions.

In fact, we saw a lift of 81.83 percent from one campaign.

But here’s the thing. You need to use popups responsibly and in a way that’s not going to create any friction. This is important for desktop users, and it’s really important for mobile users.

After all, what’s “just a pop up” for shoppers on a desktop, where it may not consume the entire screen, is often a full-blown interstitial for those using a mobile device. 

So, if you block out their whole screen, it can be incredibly disruptive and create ill will if a shopper can’t exit out of the popup and resume shopping as normal.

This begs the question. How do you use popups responsibly for mobile list building?

It’s simple. Make it quick, easy, and intuitive to close the popup. I’m going to go back to Rainbow Shops one more time for this example. Once again, here’s what their mobile opt-in looks like.

It’s a complete interstitial, where shoppers can’t see anything besides the popup. But, if they’re not interested and want to exit to continue shopping, all they have to do is tap on the “X” icon in the top right-hand corner. 

It’s prominent and conspicuously placed in a logical location, allowing shoppers to tap on it with ease. And by doing so, they’ve instantly whisked away to the regular site with zero drama. 

Just to make sure they don’t rub returning mobile visitors the wrong way, Rainbow Shops doesn’t hit them with the same pop up again after they’ve clearly shown that they’re not interested in signing up. 

Rather, Rainbow Shops has this sticky button at the lower left-hand side of the screen.

That way, the pop up isn’t annoying anyone, but if a shopper decides later on that they do want to sign up and enter to win a $500 eGift card, they can still do it. 

The bottom line here is that you can definitely use popups for mobile list building, and in fact, it’s often advisable to do so. Just remember to “be cool” about it and don’t ruffle any feathers in the process. 

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Just over half of everyone visiting your e-commerce store is on a mobile device. And that number will likely increase in the future. When it comes to getting this segment to opt-in, you need a game plan that caters specifically to mobile shoppers and hits all the right notes. 

The mobile listing building strategies I’ve covered here should get you up to speed and take your conversion rate from being just so-so to lights out. 

Which of these mobile opt-in examples did you like the best, and why?

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