The forbidden symmetry of Penrose tiles and quasicrystals.
Saturday, February 16th, 2019
Monday, January 7th, 2019
An interesting proposal from Jake on a different way of defining how service worker fetch events could be handled under various conditions. For now, I have no particular opinion on it. I’m going to let this stew in my mind for a while.
Friday, August 3rd, 2018
I got an intriguing email recently from someone who’s a member of The Session, the community website about Irish traditional music that I run. They said:
When I recently joined, I used my tablet to join. Somewhere I was able to download The Session app onto my tablet.
But there is no native app for The Session. Although, as it’s a site that I built, it is, a of course, progressive web app.
They went on to say:
I wanted to put the app on my phone but I can’t find the app to download it. Can I have the app on more than one device? If so, where is it available?
I replied saying that yes, you can absolutely have it on more than one device:
But you don’t find The Session app in the app store. Instead you go to the website https://thesession.org and then add it to your home screen from your browser.
My guess is that this person had added The Session to the home screen of their Android tablet, probably following the “add to home screen” prompt. I recently added some code to use the
window.beforeinstallprompt event so that the “add to home screen” prompt would only be shown to visitors who sign up or log in to The Session—a good indicator of engagement, I reckon, and it should reduce the chance of the prompt being dismissed out of hand.
So this person added The Session to their home screen—probably as a result of being prompted—and then used it just like any other app. At some point, they didn’t even remember how the app got installed:
Success! I did it. Thanks. My problem was I was looking for an app to download.
On the one hand, this is kind of great: here’s an example where, in the user’s mind, there’s literally no difference between the experience of using a progressive web app and using a native app. Win!
But on the other hand, the expectation is still that apps are to be found in an app store, not on the web. This expectation is something I wrote about recently (and Justin wrote a response to that post). I finished by saying:
Perhaps the inertia we think we’re battling against isn’t such a problem as long as we give people a fast, reliable, engaging experience.
When this member of The Session said “My problem was I was looking for an app to download”, I responded by saying:
Well, I take that as a compliment—the fact that once the site is added to your home screen, it feels just like a native app. :-)
And they said:
Yes, it does!
Friday, February 9th, 2018
I still find the landscape of build tools completely overwhelming, but I found this distinction to be a useful way of categorising the different kinds of build tools:
Build tools do two things:
- Install things
- Do things
So bower, npm and yarn install things, whereas grunt, gulp, and webpack do things.
Monday, November 6th, 2017
Installing Progressive Web Apps
It used to literally say “add to home screen.”
Now it simply says “add.”
I vaguely remember there being some talk of changing the labelling, but I could’ve sworn it was going to change to “install”. I’ve got to be honest, just having the word “add” doesn’t seem to provide much context. Based on the quick’n’dirty usability testing I did with some co-workers, it just made things confusing. “Add what?” “What am I adding?”
Additionally, the prompt appeared immediately on the first visit to the site. I thought there was supposed to be an added “engagement” metric in order for the prompt to appear; that the user needs to visit the site more than once.
You’d think I’d be happy that users will be presented with the home-screen prompt immediately, but based on the behaviour I saw, I’m not sure it’s a good thing. Here’s what I observed:
- The user types the URL
archive.dconstruct.orginto the address bar.
- The site loads.
- The home-screen prompt slides up from the bottom of the screen.
- The user immediately moves to dismiss the prompt (cue me interjecting “Don’t close that!”).
This behaviour is entirely unsurprising for three reasons:
- We web designers and web developers have trained users to dismiss overlays and pop-ups if they actually want to get to the content. Nobody’s going to bother to actually read the prompt if there’s a 99% chance it’s going to say “Sign up to our newsletter!” or “Take our survey!”.
- Because the prompt now appears on the first visit, no trust has been established between the user and the site. If the prompt only appeared on later visits (or later navigations during the first visit) perhaps it would stand a greater chance of survival.
It’s still possible to add a Progressive Web App to the home screen, but the option to do that is hidden behind the mysterious three-dots-vertically-stacked icon (I propose we call this the shish kebab icon to distinguish it from the equally impenetrable hamburger icon).
I was chatting with Andreas from Mozilla at the View Source conference last week, and he was filling me in on how Firefox on Android does the add-to-homescreen flow. Instead of a one-time prompt, they’ve added a persistent icon above the “line of death” (the icon is a combination of a house and a plus symbol).
When a Firefox 58 user arrives on a website that is served over HTTPS and has a valid manifest, a subtle badge will appear in the address bar: when tapped, an “Add to Home screen” confirmation dialog will slide in, through which the web app can be added to the Android home screen.
This kind of badging also has issues (without the explicit text “add to home screen”, the user doesn’t know what the icon does), but I think a more persistently visible option like this works better than the a one-time prompt.
Firefox is following the lead of the badging approach pioneered by the Samsung Internet browser. It provides a plus symbol that, when pressed, reveals the options to add to home screen or simply bookmark.
I don’t think Chrome for Android has any plans for this kind of badging, but they are working on letting the site authors provide their own prompts. I’m not sure this is such a good idea, given our history of abusing pop-ups and overlays.
Sadly, I feel that any solution that relies on an unrequested overlay is doomed. That’s on us. The way we’ve turned browsing the web—especially on mobile—into a frustrating chore of dismissing unwanted overlays is a classic tragedy of the commons. We blew it. Users don’t trust unrequested overlays, and I can’t blame them.
For what it’s worth, my opinion is that ambient badging is a better user experience than one-time prompts. That opinion is informed by a meagre amount of testing though. I’d love to hear from anyone who’s been doing more detailed usability testing of both approaches. I assume that Google, Mozilla, and Samsung are doing this kind of testing, and it would be really great to see the data from that (hint, hint).
But it might well be that ambient badging is just too subtle to even be noticed by the user.
On one end of the scale you’ve got the intrusiveness of an add-to-home-screen prompt, but on the other end of the scale you’ve got the discoverability problem of a subtle badge icon. I wonder if there might be a compromise solution—maybe a badge icon that pulses or glows on the first or second visit?
Of course that would also need to be thoroughly tested.
Sunday, December 4th, 2016
Henrik points to some crucial information that slipped under the radar at the Chrome Dev Summit—the Android OS is going to treat progressive web apps much more like regular native apps. This is kind of a big deal.
It’s a good time to go all in on the web. I can’t wait to see what the next few years bring. Personally, I feel like the web is well poised to replace the majority of apps we now get from app stores.
Sunday, October 16th, 2016
Jake goes into the details of what exactly is happening when a service worker is installed or replaced.
This is easily the most complex part of working with service workers, and I think I’m beginning to wrap my head around it, but the good news is that, for the most part, you don’t really need to know the ins and outs of this to get started (and dev tools are now making it easier to nuke from orbit if this begins to bite).
Monday, September 19th, 2016
Alex runs through the features that a progressive web app must have, should have, and would be nice to have.
In general, installability criteria are tightening. Today’s Good-To-Haves may become part of tomorrow’s baseline. The opposite is unlikely because at least one major browser has made a strong commitment to tightening up the rules for installability.
Right now, this is in the nice-to-have category:
Mobile-friendly, not mobile-only.
Personally, I’d put that in the must-have category, and not just for progressive web apps.
Anyway, read on for some advice on testing and tooling when it comes to evaluating progressive web apps.
Friday, July 22nd, 2016
The life cycle of a Service Worker—with all its events and states—is the one bit that I’ve never paid that much attention to. My eyes just glaze over when it comes to installation, registration, and activation. But this post explains the whole process really clearly. Now it’s starting to make sense to me.
Sunday, December 6th, 2015
Tim outlines the process for getting up and running with HTTPS using Let’s Encrypt. Looks like it’s pretty straightforward, which is very, very good news.
I’m using the Salter Cane site as a test ground for this. I was able to get everything installed fairly easily. The tricky thing will be having some kind of renewal reminder—the certificates expire after three months.
Still, all the signs are good that HTTPS is about to get a lot less painful.
Friday, November 27th, 2015
Bruce gives a great run-down of what’s involved in creating one of those new-fangled progressive apps that everyone at Google and Opera (and soon, Mozilla) are talking about: a secure connection, a service worker, and a manifest file.
Crucially, in browsers that don’t support it, you have a normal website. It’s perfect progressive enhancement.
Funnily enough, this here website—adactio.com—is technically a progressive app now.
At their simplest, Progressive Web Apps are application-like things hosted on your web server. If you’re as old as me, you might call them “web sites”
Tuesday, July 16th, 2013
This a great proposal: well-researched and explained, it tackles the tricky subject of balancing security and access to native APIs.
Far too many ideas around installable websites focus on imitating native behaviour in a cargo-cult kind of way, whereas this acknowledges addressability (with URLs) as a killer feature of the web …a beautiful baby that we definitely don’t want to throw out with the bathwater.
Saturday, March 24th, 2012
Press play on each video, sit back, and relax.
Thursday, October 27th, 2011
I particularly like the memetic variation of The Stallman Dialogues. There’s a real genius in the way that it quotes passages from the email verbatim.
Y’know, I’m supposed to have a Skype call with Andy sometime next week about my upcoming talk and workshop at Build (tickets are still available for the workshop, by the way). I’m very tempted to channel my inner Stallman for the duration of our conversation.
Meeting that sad animal is not an agreeable surprise.
Monday, February 16th, 2009
A beautiful video created on London's Monument. "The installation provides a live stream of continually modified time-lapse images 24 hours a day, 7 days per week. A computer controlled digital camera provides a 360-degree panoramic view from the top of the Monument."
Sunday, August 13th, 2006
Me? I'm just pee-shy. From The Meaning of Liff: KETTLENESS (adj.) The quality of not being able to pee while being watched.