Over the years, searcher's devices and behaviours have changed. More and more people use mobile devices to perform searches. Long are the days when everybody used a desktop computer. 

Google spotted this trend early. In 2015, they launched an update called the “Mobilegeddon” - which is a great name, by the way. The goal of this update was to use mobile-friendliness as a ranking factor. 

A year later, in 2018, they announced that they’d be using mobile-first indexing. Move forward to 2024; if your site isn’t accessible on a mobile device, it won’t even be indexed. That’s a huge change compared to 2015. 

What is Mobile-First Indexing 

Mobile-first indexing means that Google now prioritises the mobile version of a website's content for indexing. 

If a website has separate mobile and desktop URLs, Google will display the mobile URL for mobile users and the desktop URL for desktop users, but the content used to rank both versions will be drawn from the mobile version. 

Mobile-First Indexing Timelines 

Google has been rolling out mobile-first indexing for nearly ten years. Here’s a brief overview of the timeline: 

How Does Mobile-First Indexing Impact SEO? 

This new mobile-first indexing feature has impacted SEO greatly. If your site isn’t mobile-friendly, it won’t rank or even index—end of story. 

As of 2024, your website should be mobile-focused. Yes, it should still cater to desktop users. However, the main focus should be on the mobile interface, as this is how Google will be ranking your web pages from now on. 

Mobile-First Indexing Best Practices 

If you don’t want to be left behind with mobile-first indexing, follow the below best practices: 

1. Prioritise Mobile-Friendly Design

As you can probably guess, you need a mobile-friendly design. The best way to achieve this is through a responsive web design. A design that adapts to multiple screen sizes and orientations. 

The goal of a responsive design is to cater to all devices. Therefore, it can add, take away, or resize elements on the screen to fit a specific device. 

In general, this is much easier (and SEO efficient) than having two different URLs: one for desktop and one for mobile. 

2. Optimise Content Accessibility for Google

Make it easy for Google to understand your platform. If you’re using two different types of URLs (one for desktop and one for mobile), be consistent with meta tags like “robots” to ensure proper indexing. 

Alongside this, make sure that important content loads first. This also helps with your Core Web Vitals. It would also be best to ensure that Google can have access to everything: images, scripts, stylesheet, etc. 

3. Maintain Content Parity Across Devices

The content on the desktop version of your website should match your mobile version. 

Commonly, website owners reduce the content on their mobile versions. However, this could have adverse effects on SEO now. 

Google is prioritising content from mobile pages. Therefore, your ranking power lies in your mobile-specific pages. If there’s less content on these pages because they’re for mobile, you’ll see a drop in traffic. 

Including this, your desktop and mobile content should have unified headings and metadata. Ideally, everything should be the same apart from some elements like banners, images, etc. 

4. Implement Structured Data and Metadata Correctly

If you have structured data or metadata on your website, it should be the same on the mobile and desktop versions. If you have to prioritise the type of structured data you use on mobile, start with VideoObject, Product, and Breadcrumbs. 

5. Ad Placement and User Experience

When displaying ads on your website to a mobile device, follow the Better Ads Standard. 

Try to follow these guidelines as closely as possible. Ensure they also have a dedicated area to load to improve cumulative layout shift (CLS) results. 

6. Optimise Visual Content for Mobile

Images on mobile appear different to images on desktop. You either need to change them to suit mobile devices or only make them appear on a desktop device. 

You should also: 

• Use high-quality images 
• Use support formats or tags 
• Use static URLs 
• Use descriptive alt-text 
• Make mobile content just as good as the desktop version. 

This isn’t for images only, either. The same rules apply to videos. Ensure that your video follows the above tips, and it’ll perform much better in the search results. 

7. Speed Should Still Be a Priority 

Lastly, you should still focus on speed - just like you’ve been doing with the desktop version of your website. 

Simply put, the slower your website is, the higher the bounce rate. The higher the bounce rate, the less satisfied the searcher is, and the poorer the rankings for you. 

Make sure that you follow Core Web Vitals closely and optimise them for both mobile and desktop. 

How to Fix Mobile Indexing Issues 

Now you know the best practices, let’s audit your website to identify mobile-indexing issues. 

1. Check for Mobile-Friendliness 

One of the best ways to test your site's mobile-friendliness is through PageSpeed Insights by Google. When you use this tool, it’ll give you a mobile and desktop-friendless score. 

To perform a test, first go over to PageSpeed Insights and enter your website’s URL. Once entered, click “Analyse” 

After it audits your website, it’ll have two reports you can select between: mobile and desktop. We want to review the mobile-friendliness, so click the “Mobile” tab. 

Once clicked, it’ll show you a “Core Web Vitals Assessment”. This measures how fast and stable your site is when loaded on a mobile device. In other words, how “mobile friendly” your website is. 

Below this assessment, you’ll also find a “Diagnostics” section. These are some opportunities where you can fix some of your mobile-friendliness issues. 

Without question, PageSpeed Insights is a superb tool. The only issue, however, is that it’s pretty technical, and you can only do one page at a time - the page you analyse. 

It’s superb for small websites or for website owners on a budget. However, if you have the budget, we recommend that you use an SEO site audit tool. 

2. Perform a Site Audit 

There are a ton of site audit tools available nowadays. Some are expensive, and some are much more affordable. Whichever you choose is entirely up to you. 

Whoever you decide to go ahead with, it should be pretty straightforward to perform a site audit. All you need to do is go over to the site audit feature and enter your URL. 

From here, the SEO tool will perform a site audit. Once performed, it’ll give you various metrics, such as site health, mobile friendliness, errors, etc. 

Go to the mobile-friendliness report and see what mobile problems you have with your website. For the most part, SEO tools will also give you instructions on how to fix them. 

Alternatively, you could just Google the problem. There’ll be an answer online. 

Staying Updated with Future Indexing Updates 

If you’ve had a website for a long time, the best time to start optimising for mobile-first indexing was almost ten years ago. Because of this, it’s extremely important to stay up to date with Google updates. 

To stay updated with large changes like this, we recommend you follow the Google Search Central Blog. This is Google’s official blog; they post all their updates and recommendations there. 

Conclusion 

After reading the above, you should have a much better understanding of mobile-first indexing. Though it’s been a slow implementation, in 2024, it’s finally here, and it overrides desktop-first indexing. 

If you haven’t started focusing on mobile user experience, you now need to. If you haven’t, you may even have experienced a drop in traffic - and this is the reason why. 

Therefore, start focusing on mobile. Don’t neglect the desktop, as it’s still important. However, have a special focus on mobile to ensure you’re taking advantage of the new mobile-first indexing feature.