Read Time: 8 min

The Ultimate Guide to Email on Android


Building emails that perform well on mobile is key for every email marketer—and with that, optimizing for Android environments has become more and more crucial. Google’s Android is the world’s most popular mobile operating system, followed by Apple’s iOS.

But building emails that look great on Android devices is hard!

That’s because there isn’t just one Android environment to optimize for, but a highly fragmented market that challenges every email marketer who aims for a consistent experience for all subscribers.

How does your email look on Android?

Litmus offers the most extensive set of Android clients for email testing. Make sure your email looks great in the most popular Android environments, including:

Android 4.4 Native Email Client
Android 5.1 (Vanilla)
Android 6.0 (Vanilla)
Android Gmail App (Gmail accounts)
Android Gmail App (IMAP accounts)

Sign up now→

What makes building email for Android so tough? There are three key factors that impact how your email renders on Android: the Android operating system (OS) version, the app or email client your subscribers use, and the size of the screen your email is viewed on.

Let’s look at them one by one:

1. The Android Operating System

Like any other operating system (OS), Android comes in different versions. Unlike Apple’s iOS, which enjoys high adoption rates as soon as Apple releases a new version, many Android devices are not eligible to upgrade to newer OS releases. As a result, it’s often not the most recent operating system that powers most Android devices, but a mixture of older Android versions.

Android 5 Lollipop, first released in November 2014, is currently the most popular Android OS, with 33% of all Android devices running this version. Android Marshmallow (first released in October 2015) ranks second with a market share of 31%, followed by Kitkat, a fairly old OS from 2013, that still powers 22% of all Android devices. In contrast, Android Nougat, Google’s most recent release (October 2016), currently only accounts for 1% of all devices.

Android platform version market share
Android platform version market share. Source: Android Developers

If you were to dig deeper into these numbers, you’d see that the popularity of versions of Android varies across countries, too.

Android platform market share by country
Source: Device Atlas

As a result, email designers who build email for an Android audience not only have to optimize their messages for the most recent Android release, but for a whole set of popular versions of Google’s operating system. And—you might have already seen this coming—each OS version comes with its very own rendering quirks.

2. The App or Client

When we talk about email on Android, we also have to distinguish between different email clients.

The Native Email App

Google’s stock email app that comes with the Android operating system, came preinstalled on all Android devices running on Android 4.4 (KitKat) and below. Vendors who wanted to run their devices on the Android had no choice but to provide the Android native email client as well.

However, starting with Android Lollipop (5.0), Google has nixed out-of-the-box support for its native email app, making it possible for vendors to use Android without being forced to integrate the default apps.

While the native email app is no longer installed by default on all Android phones, Google’s apps developed for Android remain available as open source to vendors and the public. Vendors, like Samsung or Sony, are free to use Google’s so-called “vanilla” version of the email app and make any changes they like—or develop their very own email app from scratch.

This has lead to even more fragmentation in the Android email client market.

The Gmail App

The Gmail app is Google’s new default email app that is pre-installed on many Android devices.

In contrast to the native Android email app’s solid HTML and CSS support, the Gmail app has caused email marketers headaches in the past. Similar to Gmail’s web client, the Gmail app on Android was known for its poor HTML and CSS support.

In September 2016, however, things changed. The massive update to Gmail’s rendering engine also applied to its mobile application, allowing email developers to take advantage of responsive email design, advanced font styling options, and improved support for CSS.

Rendering Trouble with IMAP and POP Accounts in Gmail

There is, however, one exception: Google’s improved rendering engine does not apply to POP/IMAP accounts using the Gmail app. These are non-Gmail email accounts (such as,,, etc.) accessed through the Gmail app via POP and IMAP.

In this case, Gmail still relies on the old rendering engine and its lack of support for CSS and media queries. Users who use a Gmail address and G Suite will enjoy responsive design and advanced CSS support—users who use a non-Gmail address, on the other hand, will not.

Email developer Rémi Parmentier took a deep dive into the different types of Gmail accounts and how email rendering differs per account.

The significant inconsistencies in rendering for Gmail and POP/IMAP accounts have caused lots of confusion in the email world. To clear things up, here’s how rendering in a classic Gmail account compares to its IMAP or POP counterpart:


Gmail (IMAP)

The Basics

Style support in head


Media query support


CSS attribute selector support






Images and Visuals

Images enabled by default?


Animated GIF support


ALT text support


Styled ALT text support


Background images support


HTML5 video support














Web fonts


Progressive Enhancement

Border Radius


Interactivity — checkbox/radio button support


Animation — transitions/keyframe animation support


Is your brain hurting already? Take a deep breath and stay with us, because there is one more thing you need to know.

Device Screen Size and Resolution

With Apple’s iPhones, understanding screen sizes is simple. Since the release of the first iPhone, there are only 13 different devices with seven different screen sizes and six different resolutions. Compare this to Android, which has over 4,000 devices in circulation with a multitude of screen sizes and resolutions.

Android device screen size fragmentation vs. iOS devices
Android device screen size fragmentation vs. iOS devices from OpenSignal

Why does screen size and resolution matter for email marketers? Screen size will give you an indication of which media queries to use if you want to optimize for a certain set of devices. The more screen sizes you’d like to optimize for, the more complex your media queries will get.  

How should you handle the Android madness when coding email?

As the world’s most popular mobile operating system, Android can’t be ignored by email marketers—even though the heavy fragmentation makes optimizing emails for Android environments a pain.

But how do you tackle the complexities of making email work for Android devices? Here are some tips to get you started:

    • Understand Android usage in your audience
      Use Litmus Email Analytics to better understand your audience: Do your subscribers open email on mobile, and if so, are they opening on Android devices? Looking at this data helps you set priorities to make sure you’re only spending time and effort on the Android versions, clients, and screen sizes that really matter to your audience.
    • Build mobile-first with coding methods such as hybrid coding
      Both hybrid coding and the Fab Four Technique are flexible coding techniques that do not rely on media queries to resize and change the email width for different device sizes—a perfect approach if you have to support a broad range of Android device dimensions.
    • Have fallbacks in place when using progressive enhancement
      Almost all Android clients lack support for advanced enhancements like web fonts or interactivity. When using those techniques, make sure you have appropriate fallbacks in place to ensure that your email looks great when opened on Android.
    • Keep your code clean and concise
      Coding for email requires a certain amount of repetition, especially when inlining styles. This can lead to bloated code and large file sizes. The Gmail app clips emails over 102kb, which can lead to emails that look broken. Make sure your inline styles are defined only where needed to avoid unnecessary repetition.
    • Test your email before you send
      Building email for Android is hard, but thorough testing can help you send with confidence. Litmus lets you preview your emails in 70+ clients and devices, including popular Android environments.

See your emails in Android devices

Preview your emails in popular Android environments, along with over 60 other email clients and apps, with Instant Previews in Builder and Checklist.

Try Litmus free →