Content Guidelines for Better Conversions

Joel Oliveira
Joel Oliveira
Dec 13 2021
Posted in Best Practices

A few tips to make faster and better campaigns

Content Guidelines for Better Conversions

It doesn't matter how easy our platform enables your creativity or how fast we deliver your messages. Your content is still the most important factor for the success of your campaigns. A good copy that connects with your audience, engaging media that stands out, and functionality that enables a seamless experience should be a brand's top priority.

But with an increasing wide range of devices, varied download speeds, and multiple channels to support, it's essential to get your basics right. And in this post, we will address just that.

App Push Notifications

Mobile apps are feature-rich, and in Notificare, we take this to a whole level. Besides supporting all the goodies both iOS and Android provide, we also extend on those features with unique functionality that helps you take your campaigns to a whole new level. Things like rich content (HTML, Webpages, Images, Videos, Maps, etc), native functionality (collect text and media from user's input) or automatic segmentation based on how users interact with your messages.

All this is important, but if you fail to get the basics right, your campaign will never take full advantage of all these features. Here's how you can make sure you nail all those little things that make up a good push notification:

Character limits

Push notifications should be short and easily consumable. If your content requires more, you can always use our rich notification types to include more content using many different formats.

The following values are approximations of how different platforms handle push notifications. Emojis count as one character and are controlled by the operating system. Make sure you use Emojis that exist on all platforms.

Android≈50≈150 - max. 1 line
iOS≈20-50≈150 - max. 4 lines
Recommended for all≈20≈60

Secure Content (HTTPS)

Notificare provides all you need to create secure content served over HTTPS. Our message and content editors will allow you to upload any type of media and we will happily host it all for you. Features like Links or Personalized Content will also enable you to host content over a secure protocol.

If you do host your own media, make sure your URLs use HTTPS and that they are publicly available.

Lock Screen Images

Including images in your push notifications are a great way of creating engaging content. Several studies reveal that messages with lock screen images convert 50% better than only text.

The following values are recommended for a good user experience.

PlatformFile TypesImage Dimensions (px)File SizeAspect Ratio
AndroidJPEG, PNG and GIF (static)min. 600 x 300 - max. 2048 x 1024≈300Kb up to max. 2MB2:1
iOSJPEG, PNG and GIF (static or animated)min. 300 x 300 - max. 1038 x 1038≈300Kb up to max. 10MB1:1, 1:2 or 2:1
Recommended for allJPEG and PNG720 x 360≈300Kb2:1


Push notifications support sounds. It is an excellent way of getting attention from your users. By default, none will be defined, but you can use default to trigger the system notification sound.

Custom sound files are also supported, this will allow you to create a personalized experience, but your apps will need to include those sound files.

PlatformFile TypesNotes
Android.wav, .mp3 and .oggAndroid users can override app generated sounds
iOS.wav, .aiff and .cafFiles must be less than 30 seconds long and properly encoded (Linear PCM, MA4 (IMA/ADPCM), µLaw, or aLaw)

Web Push Notifications

Just like in native mobile apps, the Notificare SDK for websites, will also allow you to extend the browser's push notification capabilities with more functionality.

Because each platform uses a different visual layout for messages, the amount of content that is visible varies. This is substantially more important on the web than on native apps.

Character limits

Web push notifications should also be short. The following values are approximations of how different platforms handle push notifications. Emojis count as one character and are controlled by the operating system. Make sure you use Emojis that exist in all operating systems.

Windows: Chromium-based≈40 - 60≈120 - 150
Windows: Firefox≈40≈140 - 190
Mac: All browsers≈20 - 40≈20 - 80
Recommended for all≈20≈60

Lock Screen Images

Including images in your web push notifications is also supported in all browsers, except Safari. However, browsers will display them differently depending on the operating system.

Operating SystemFile TypesImage Dimensions (px)File SizeAspect Ratio
WindowsJPEG, PNG or static GIFmin. 600 x 300 - max. 1024 x 2048≈300Kb up to max. 2MB2:1
AndroidJPEG, PNG or static GIFmin. 600 x 300 - max. 1024 x 2048≈300Kb up to max. 2MB2:1
MacJPEG, PNG or static GIFmin. 300 x 300 - max. 2048 x 2048≈300Kb up to max. 2MB1:1, 1:2 or 2:1
Recommended for allJPEG and PNG720 x 360≈200Kb2:1


Email campaigns are still one of the most effective channels out there. With Notificare, you can enjoy all the great functionality like advanced audience selection or automatic segmentation.

It's also important to highlight that emails can be consumed on a variety of devices. Responsive email design is not recommended; it is mandatory. In Notificare, our Drag & Drop editor will already take care of this for you, but you should take that into consideration when crafting your custom HTML content.

Similar to other channels, it's always a good idea to keep email images as small as possible, no larger than 200K, whether that's a JPG or PNG, or a static or animated GIF. Also, make sure your images are twice as big as the content you are trying to fill. This will make sure they look great on high-definition screens.

Subject Lines & Body Length

A successful email campaign starts with a great subject line. Add some kind of personalization, be direct and descriptive, short and concise, and careful with your use of punctuation and Emojis. All this plays a huge role in how your messages perform.

Subject9 words or less
Body≈100Kb to prevent Gmail clipping
Images≈200Kb max. size and 2x bigger than allotted space

This is why testing your content is extremely important. With Notificare, you can test your email messages in more than 90 email clients running on real devices. More information about Email Proofing can be found here.

Link Tracking

Notificare also provides link tracking by default. In most cases, this is how you will measure the success of your campaign. Especially with email clients progressively adopting mechanisms that stop you from measuring the open rates, measuring the clicks is, by far, your most important KPI.

But there are cases where measuring clicks might just prevent some functionality from working as it should. In those cases, you might want to opt-out from that altogether by using the following option:

Disable Link Tracking

Or on a per-link basis by using a recognizable query parameter in your links:

<a href="">Original URL</a>

This is an important step, specifically if you are using our Universal Links or any other similar product.


Notificare's email messages can also contain attachments. This is an extremely useful feature, especially for transactional emails, like order confirmations with invoices or product sheets. However, some limitations are in place, and you should not include files bigger than 2MB. Although many email providers will allow bigger attachments, this limitation will ensure your messages have a better chance of being accepted by ESPs.


SMS is by far the best-performing messaging channel. Currently, Notificare does not support MMS; therefore any type of content other than text is not supported.

Character limits

An SMS message is technically 160 characters. This protocol was originally designed to send and receive short messages, basically, 160 7-bit characters, which means 1120 bits, or 140 bytes. The 160-character limit is for messages encoded using the GSM-7 character set. Messages that use at least one single character that is not GSM-7 (UCS-2), are limited to 70 characters.

However, most modern phones and networks support message concatenation. Basically, they split larger messages into smaller parts (segments) before sending and phones are able to re-create them at the receiving end. Notificare will bill you every segment, therefore you might want to pay attention to the text you are sending, as removing any UCS-2 characters (if possible) might present you some savings. For example, changing to " will prevent you from having a UCS-2 character that would limit your message to 70 characters.


Using short links in text messages is a great way of redirecting users to content that would never fit in this short format. As mentioned before, Links are a Notificare feature that allows you to create short URLs that can redirect users to other web pages, host custom static HTML landing pages, or provide support for Universal & App Links.

These links will also collect useful metrics, trigger automated follow-up campaigns, or even automatically segment your users.


This should be a good starting point for those of you looking for some guidelines and common best practices for messaging campaigns. We still encourage you to always test on real devices, when possible, and in case of doubt, feel free to drop us a message via our Support Channel.

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