Software Walker

Alexandre is giving a great overview of the history of JavaScript, popular API’s, and the role of W3C and other standards bodies. He gives a shoutout to Kevin Dangoor for CommonJS, then proposes the idea that remote CommonJS processes can be thought of as remote Web Workers. Wakanda makes big use of CommonJS.

Josh Powell is giving a great talk about how to make single page web applications with JavaScript. The main focus is on how to break free of the web 1.0 tyranny of doing a page load for every new piece of content. He says his big AHA moment was to hang a handler off the jQuery hashchange() function; this lets you put a router on your client side; you can show different content based on the value after the hash without page loads, and your browser history buttons will work properly. Cool stuff.

This session has David and Josh riffing about designing for mobile.

Device context is different from User Context. Just because you know they have a small screen, you don’t know whether they’re focused or distracted, having a short or a long interaction.

Omitting content from the mobile version of your site is like an author looking at the paperback edition of their book and saying, “it’s smaller, I should leave out some chapters” — Josh Clark

Example: alibris.com omits their key differentiator, Rare Books, from their mobile site. Are we really sure people don’t want to buy rare books from their phone? 28% of mobile web users only surf from their phone. Phones are peers to our other devices, not just little siblings.

Example: The original Bank of America app showed you your balance and had a logout button. That was it.

Touch is only the current thing we want to figure out. Coming next are speech recognition, gesture recognition. Note: speech plus gesture recognition equals Harry Potter territory!

David Kaneda is talking at DevCon5 NYC talking about cross-device development:

* You only get access to four touch events on most devices right now. See Boris Smus’s pointer.js as a nice abstraction layer. Enhance your hit radius for touch to make it easier to touch your target.

* Scrolling is really hard. You need a library like Swipe.js or iScroll to give you the momentum and friction physics that you get on iPhone. Of course, David thinks Sencha Touch is the best; he’s biased, since he spent months working on scrolling as part of the Sencha team. (Note: unfortunately, Sencha doesn’t support Gecko).

* Beware of measuring distances in pixels. Retina displays automagically compensate when you use pixel units in CSS, Android does not.

* Read the user interface guidelines for iOS, Windows Metro, Android. For example, iOS uses Sheets where Android uses Overlays. Standard icons for stuff like Reply, Trash, Bookmarks, Back are all different. Try to follow the platform-specific conventions (i. e., don’t be a tourist) and leverage the universal stuff.

* Buy some devices! Hold onto your old phones, use them for testing. Don’t upgrade the iOS on your old phones, it’s hard to go back. Buy old phones from your friends. Pay to attend Google I/O.

* Lots of mobile interfaces are heading towards type-based minimalist interfaces while iOS becomes elaborate and skeuomorphic. For example, the iOS Address Book interface makes non-geek users comfortable right away. The minimalist interfaces seem like they’ll be a lot more portable, but for complex desktop Apps it may not scale up to having toolbars with 40 icons.

* Use CSS to give yourself various fallback positions for fonts, backgrounds [but beware the performance hit of fancy CSS].

* Sometimes, you just have to use User Agent detection (followed by tagging DOM with platform-based classes and then fixing it all in CSS).

Greetings from DevCon5 NYC. Our morning starts with Peter Lubbers giving an HTML5 overview. He’s reminding us about some important fundamentals:

* Web Origins (see RFC 6454) are everywhere. You need to understand not only how they regulate JavaScript execution, XMLHttpRequests, LocalStorage. Be sure to understand and specify Cross-Origin Resource Sharing (CORS) policy.

* Investigate Web Intents as a way to better integrate Apps and avoid clunky workflows and/or reimplementations. (note: more standardization is needed here)

* Learn about real-time connectivity options, including cross-document messaging using postMessage, XMLHttpRequest level 2, Server-sent Events, WebSockets, and even WebRTC.

* Learn about browser compatibility at caniuse.com, mobilehtml5.org, and at MDN

* Be inspired by great demos of WebSockets, WebGL at http://kaazing.com/demos