The Mobile Performance Inequality Gap, 2021
Alex Russel, a lead performance developer at Google is a firm believer in “an internet for everyone”. He highlights this in a poignant Chrome Dev Summit talk in 2016 where he showed that when we construct the digital world to the limits of the best devices, we build a less usable one for 80+% of the world’s users.
Since things have changed since 2016, the updated golden web performance standard to achieve now is ~100KiB of HTML/CSS/fonts and ~300-350KiB of JS (gzipped). This rule-of-thumb limit typically lasts about two years and is a hard target to meet. Most modern development tooling easily surpasses this amount in lieu of providing a robust and intuitive developer experience but there is a high cost in doing so if you’re attempting to cater to an international market, as the data suggests.
Your company’s poor site performance can manifest as lower engagement, higher bounce rates, or a reduction in conversions.
The harmful business impact of poor performance is constantly re-validated. Big decreases in performance predictably lead to (somewhat lower) decreases in user engagement and conversion. The scale of the effect can be deeply situational or hard to suss out without solid metrics, but it’s there. When doing user research, Google’s Web Team found some interesting patterns:
Users hate delays and unreliability on mobile: the level of stress caused by mobile delays is comparable to watching a horror movie.
Fifty percent of smartphone users are more likely to use a company’s mobile site when browsing or shopping because they don’t want to download an app.
One of the top reasons for uninstalling an app is the limited storage (whereas an installed PWA usually takes less than 1MB).
According to those observations, Google found that customers prefer experiences that are fast, installable, reliable, and engaging (F.I.R.E.)! This means companies need to be laser-focused when it comes to performance budgeting. Check out the average device capability worldwide.
From 2017 data, the default global baseline is a ~$200 Android device on a 400Kbps link with a 400ms round-trip-time (“RTT”). This translates into a budget of ~130-170KB of critical-path resources, depending on composition — the more JS you include, the smaller the bundle must be.
The single most important thing to understand about the landscape of devices your sites will run on is that they are not new phones. Two numbers set the stage:
The median user is on a slow network. Just how slow is a matter of some debate.
This makes some intuitive sense: smartphones are not in their first year (and haven’t been for more than a dozen years), and most users do not replace their devices every year. Most smartphone sales today are replacements (that is, to users who have previously owned a smartphone), and the longevity of devices continues to rise.
PWAs leverage modern web capabilities
How we can solve this issue of performance inequality is by recognizing the issue within our own products and services and using Progressive Web Applications as a way to overcome some technical obstacles and deliver performative, highly optimized apps quickly and effectively. PWAs provide a set of best practices and modern web APIs that are aimed at meeting your customers' needs by making your site fast, installable, reliable, and engaging.