Progressive web apps explained

08th February 2016

What's all the fuss about?

In recent months, there has been an increasing amount of hype about ‘progressive web apps’. If you believe the hype they will move the mobile web forward in leaps and bounds, make web apps equal to native apps (the ones you install on your phone) and help developers and start-ups reach more customers out with the walled garden of the app stores.

So, what is a progressive web app?

The simple, non-technical explanation is that they offer ‘a new way to deliver amazing user experiences [to mobile users] (Source: Google Developers)’. This offers a new path for many businesses and start-ups who ponder whether to build a native web application for Apple, Android and Windows or to build a web application accessed directly via the web browser on a mobile phone (or both). There is a parallel here to the situation 10 to 15 years ago when a separate investment was justified in building a separate mobile website before the advent of Responsive Web Design (anyone remember WAP sites?).

The technical explanation is that in 2015, designer Frances Berriman and Google Chrome engineer Alex Russell coined the term "Progressive Web Apps" to describe apps taking advantage of new features supported by modern browsers (Source: Wikipedia). The characteristics of these are as follows:

  • Browser agnostic – they work across all browsers
  • Responsive – fit any screen size or resolution
  • Connectivity independent – they work offline or on low speed networks
  • App-like – they feel like a natural / immersive app on the device
  • Constantly updated – update in the background
  • Safe – delivered using secure protocols
  • Discoverable – identified as applications by the search engines that find them
  • Re-engageable – support features such as push notifications
  • Installable – allow users to keep apps on their home screens without the hassle of app stores
  • Linkable – easily shared via a link (URL) and easy to install

The web app manifest

A really important aspect of this is the evolving web app manifest (currently in draft) with the W3C – the international standards organisation for the web. This allows developers to write a manifest.json file and link it from the main HTML file of their progressive web app. Result? A web app that can be installed on to the mobile user’s home screen just like a native app. Granted there is more to it than that but it is beyond the scope of this article to go into the details of concepts like Service Workers and App Shells.

At Metadigital we have always been advocates of building applications based on pure web technology (such as our own Metaware). As things stand it’s clear that there is still a massive appetite for the native app store distribution channels offered for iOS, Android and Windows. However, it’s exciting to think that the pendulum is starting to swing in the other direction and that users may be able to discover progressive web apps directly through search engines and avoid app store advertising. In the near future entrepreneurs and business owners may be able to avoid the commission paid to the app stores and the cost of building separate versions of apps.

Get in touch with us if you would like to discuss how Metadigital can help you work smarter.

By: Robin Balmforth

If you'd like an informal chat about how Metadigital can help with your digital project please get in touch.