Your Guide to Designing Ads for Mobile

Illustrative graphic of a person looking on their mobile device and seeing an ad

If I asked you what the weather was going to be this evening, how would you find this information? Would you look out the window? Turn on the TV and check the news? Chances are you’d pull out your phone and run a quick search.

Even though you’re just looking for the weather, by accessing your smartphone, you are exposed to a number of opportunities for additional information. Beyond the specific info you are looking for, you are exposed to an array of ad placements—garnering a significant opportunity for advertisers.

People have access to an endless amount of content right in their pocket. Most people who own and operate a smartphone will spend an average of 3 hours on their device. Not only are users able to perform that quick search to figure out the weather, but often they are browsing out of habit, whether to pass the time or simply be entertained. It’s no question that we rely on our mobile devices for instant access to information and entertainment—at any and all times.

Back in 2019, the number of mobile phone internet users in Canada amounted to 26.1 million people. By 2023, it is expected to grow to about 30.9 million. This mobile phone usage consists of time spent playing games, browsing the web, engaging in social media, reading blogs, watching videos, and consuming other forms of content. When using their mobile devices, consumers are likely to spend 87% of their time in apps versus in their browser, a number which is expected to grow.

Knowing that all of this time is being spent on mobile devices, it is important that advertisers consider the medium through which users are consuming content and create ads specifically for this device type.

This will not only accommodate the differences in ad specifications, such as ad size, but also consumer mindsets. When you’re checking the weather on your phone, you are in a completely different frame of mind than if you were to look further into weather patterns for a report.

Mobile Ad Design vs Desktop Ad Design

The first and most obvious difference is screen size and orientation. Content is now being viewed primarily in portrait mode, whereas before it would be seen in landscape. Content that is created taller than it is wide provides a better experience for the user.

Additionally, desktop monitors can span 30 inches wide at 4k resolution, with processors that can render content quicker than a mobile device. Although mobile tech specs are smaller than those on desktop, mobile devices are still exceptionally powerful. Understanding these differences means you can design your ads so that they are appropriately optimized for smaller screens and processors.

Aside from their tech differences, consumer behaviour also changes when they spend time on mobile versus desktop. While desktops are usually used for long periods of time in one sitting, mobile users are on the go. Their total usage at the end of the day may span several hours, but that is an accumulation of shorter and more frequent uses. These short and frequent uses mean that your ads have to be compelling and eye-catching to capture the attention of a user in a matter of seconds—they may be only dedicating a few minutes on their phone while they’re in between other tasks, so time is of the essence for a mobile ad.

People also pick up their mobile devices with a different intent than if they were to log on to their computer. Phones are rarely used for making large purchases, and instead are used when conducting research on a certain product or brand. This is important as you build your overall digital strategy, as you want to consider using mobile as a top-funnel tactic.

Knowing that mobile outreach is mainly for awareness and bringing users into the top of the funnel, it is important to cater your messaging to this product or brand introduction stage. Remember, mobile advertising is part of your campaign’s entire journey and is not a standalone piece.

Your mobile ad should intrigue your prospects and encourage the user to pursue further investigation—whether that be from their mobile or desktop device. Mobile will bring users into your funnel, building an audience group to later retarget on multiple devices, including desktop. This is one way you can maximize your conversion potential. 

Making Ads for Mobile

To accommodate users who are on the go, make your ads short and catchy so they can understand your ad effortlessly. The rule of thumb is less is best, and bigger is better. This means cutting down on the amount of copy you would normally include in a desktop ad, and focus on larger imagery and typography. It has been found that using larger and wider font sizes makes content glanceable, and therefore more easily understood without needing the viewer’s full attention. 

When creating the type elements on your mobile ad, best practice for mobile websites is to have a minimum font size of 12pt and a maximum of 20pt. Anything below or above this recommendation can affect the ad’s readability. Visual hierarchy is especially important for mobile ads as you are trying to convey the same message using less content. Additionally, mobile processors are smaller than desktops, so without sacrificing quality, use images and videos at a lower resolution to save load time.

Let’s take a look at an example. A half-page unit (300×600) is a common size for a desktop ad.

However, it is far too large for a mobile device, so we will recreate this ad in two mobile-friendly sizes: 320×480 and 320×50.

The 320×480 ad size will be similar to the 300×600 ad unit above, although optimized for mobile screens.

The 320×50 ad size is much smaller, so you need to make better use of the space, and keep only the elements that matter.

Even before seeing the creative, you probably noticed the difference in the ad heights. Our goal is to cut out as much content as possible to allow room for the primary message. However, we can’t cut out too much or else the consumer will have no context to the ad’s message.

The first thing to remove is the romance copy. Although it is nice to have when there is enough space, it is not worth keeping if it prevents the main message from being readable. If there are certain elements that cannot be removed, consider replacing them with icons or symbols to save space. In this case, we are replacing the Learn more CTA with an alternate button. It still infers the same course of action, but it helps save space in the ad.

Example of an ad served on a desktop screen vs a mobile screen

Mobile Exclusive Ad Opportunities

Designing for mobile is one way to maximize your campaign’s success on these devices, but you should also consider designing ads that are made for—and only for—mobile. One channel that is offered exclusively for mobile devices is rewarded or opt-in video. This ad format appears in-app for mobile games, and incentivizes users to watch a video ad in exchange for a reward.

For example, if a user is playing a game with a limited amount of lives, they can choose to watch a video ad to receive an extra life in their game.

Ultimately, rewarded videos provide a winning scenario for all parties—brands win as they gain exposure through a new channel, consumers win as they get something in return for their attention, and publishers win as they expand into a new format that audiences find enjoyable and engaging. 

Another example of a mobile only ad format is the swipe functionality. This matches a mobile functionality users are familiar with, and works well to integrate with other content they consume.

Even with smaller screen sizes and short attention spans, there are many options available to maximize your ad exposure on mobile. When creating a well-rounded experience in a consumer’s entire purchasing journey, mobile plays an important role in the introduction and brand awareness phase.

Not to mention the sense of immediacy mobile phones provide, meaning the user can go from discovery to research in a matter of seconds. Our phones are used on a daily, if not hourly basis, and it’s important to keep that top-of-mind to reach the modern day consumer.

Want to run exceptional programmatic campaigns? Request a demo to learn more about StackAdapt.

Carolynne Wong
Carolynne Wong

Creative Strategist


Carolynne has 6+ years of experience working in dynamic creative teams, bringing a creative and process-driven approach to every project. She enjoys the challenge of making something out of nothing and helping brands develop creative campaigns.