Tag: web

What all mobile web devs should know about PhoneGap

If you already building or looking into getting started with mobile web applications you should understand the basics of PhoneGap. The name ‘PhoneGap’ is widely recognized, and perhaps more widely misunderstood.

The nudge to write this article was born out of conversations where we stumbled across concrete limitations to modern responsive JavaScript libraries such as bootstrap and jQuery. Limitations that cannot be overcome by adding more brilliant functionality because some JavaScript capabilities simply do not exist within the browser today. Furthermore, other requirements were imposed by political realities, timeframes and expectations.

That’s where PhoneGap steps in. 

So what, tell me what PhoneGap does?

PhoneGap is owned by Adobe and it has an open source top-level Apache Foundation sister project called Cordova. I won’t bore you with its long and twisted history, you can read about it here if you want.

The bottom line is PhoneGap allows you to develop JavaScript mobile applications that have access to certain aspects of the native device such as writing data to a filesystem. Your web application is wrapped within a native mobile application container that gives you JavaScript access to native operating system capabilities beyond what the browser itself is capable of doing!

By native I mean iOS Objective C, Android Java, WindowsPhone, Windows 8, Blackberry 10, Amazon Fire OS and Tizen. Your JavaScript applications runs in a chrome-less browser that gives you special hooks to the operating system. You can also submit PhoneGap applications to the AppStore, Google Play and others.

Who uses this stuff, well you may be using a PhoneGap app from one of these online stores and not even know it. To mention a few: Southwest Airlines and many others.

What limitations can PhoneGap address that responsive libraries don’t?

If your requirements call for all or most of the following items, then PhoneGap is the correct choice for your project today. That may change as HTML5 continues to rapidly grow, but for now I’m sticking with the following bullet points. Stick with me and read through all of these before starting to throw out counter arguments.

JavaScript skillz. If you are an existing JavaScript shop, then PhoneGap leverages your existing JavaScript skills to access capabilities beyond current browser functionality without the need to have an in-depth understanding of Objective C or Java.

Sure, it’s easy to say you can hire expert contractors to develop iOS and Android applications, along with UX designers and testers. But, if your budget doesn’t include the capital costs for these folks and all you have is JavaScript ninjas on staff then the choice is easy.

Or, maybe you have genius-level developers that could easily and quickly spin up on all your need to know on ObjectiveC and Java Android. If this isn’t the case, and your timeframes and budgets don’t allow for this then you’ll need a fallback plan such as PhoneGap.

Access to camera.  Yes, you can currently access the camera on some web browsers today. However, the support on mobile browsers is still inconsistent, limited or non-existent. On the other hand, native device OS’s are expected to have access to cameras If they didn’t it would be considered a serious oversight. PhoneGap provides cross-platform mobile device access to the camera.

Read/write access to SD Card. Just to reiterate, this is both read and write access to a local storage device. Certainly there is a FileReader API in plain old JavaScript, but as far as I know there isn’t a FileWriter or its equivalent yet. If you need the write access to go along with read capabilities then you should be looking at PhoneGap.

[Correction Jan. 27, 2014] I mis-wrote. The FileWriter API exists however it has limited supported across browsers: https://caniuse.com/#search=filewriter. And, examples of it’s use can be found here.

AppStore or Google Play. If you have a requirement to submit your application to the app store then PhoneGap will help you get there. There is no way today for submitting a stand-alone web application for acceptance on AppStore or Google Play. Period. Some will argue that the need for using these online application stores is going away, but that’s a non-issue if you have been directed to meet this requirement a.s.a.p. and your job depends on it. If that’s the case, then PhoneGap will be your friend.

Is there anything else I should know?

Yes…First, PhoneGap is not perfect, but then again few software projects are perfect. You will need to install and know a few things about the native IDEs you want to support. If you want to deploy Android you’ll need to install Eclipse or IntelliJ. For iOS you’ll need to install XCode. Etc. You still have to compile a native project or you can try your hand at Adobe’s PhoneGap Build, which is a cloud based build system for PhoneGap.

It is confusing that there are two projects that share a common/similar code base: PhoneGap and Cordova. Also, Cordova’s documentation has typically been more up to date that Adobe’s. If you do your research you’ll find various performance complaints and bug issues (like I just said are there any software projects that don’t have these??).  Yet, overall it’s a great starting point if you have the needs listed above, and it’s much better than trying to start from scratch given today’s dramatically shortened delivery expectations.

You can absolutely still use bootstrap, jQuery and other JavaScript libraries within PhoneGap. There are caveats, of course, related to application life-cycle issue, navigation as well as App Store and Google Play user interface acceptance guidelines.

If you want to add functionality to PhoneGap because you find some critical thing is missing that you need for your project, the good news is you can develop a custom plug-in.

Last, I should mention Titanium Studio. It also lets you leverage JavaScript skills, with the primary difference being that it converts JavaScript into native byte code rather than just displaying it in a chrome-less view.  Plus it’s comes with its own IDE and MVC Framework.  I’ve never used Titanium so I can’t judge it, however I know people who do use it successfully and love it. It’s one more thing to consider that you should be aware of.

References

Cordova Documentation

PhoneGap Documentation

PhoneGap Platform Support

The Art of Internet Connectivity

Everyone’s internet connectivity experience is unique and it can vary from minute to minute. Most internet users can sense slowdowns, and everyone can identify when a connection fails. Web developers absolutely rely on a web connection to build web pages. So, when our internet connection goes down our productivity comes to a halt.

I’ve lost count of the number of times I’ve reported to various tech support organizations that I wasn’t able to reach a particular website or web service and was told by the tech: “I was able to reach it just fine.” This happened again today when I called my DSL provider to inform them our internet service went down completely and then was degraded to 1/10 of what we were paying for (e.g. ~1.12 Mbps on a 12 Mbps service). They told me that the line was stable. Although I’m not real sure what stable means. Then the speed gradually increased back up to normal of over the next hour and a half. This has happened about a half dozen times over the last three months. 

As a web developer, you load web pages up to several hundred times per day. I almost always have monitoring tools hooked up that give the exact time to download a page and its associated elements. So, I have a good idea of when the internet is performing well, and when it isn’t.  Because of this I’ve become sensitized to small, millisecond changes in download times.

I also gained extensive knowledge of internet connections when working on high availability systems with up to five-nines uptime. We deployed systems that monitored web traffic all over the U.S. 24×7. I was amazed to see that internet traffic was very much like our roadways. Sometimes traffic is moving fast, other times it’s slow in spots, and sometimes it’s completely stopped or even re-routed.

In many cases, a modem (or router, as I’m using the terms interchangeably) simply locked up. This is quite common as these devices often run a small linux-based operating system that can occasionally flake out. I can say with certainty in the cases where my DSL modem/wireless router didn’t die, and there was no internet connection, then in 9 out of 10 of these cases it was a problem upstream with the carrier.

Guidelines. So, here are some guidelines for helping you narrow down where the problem might be:

– Check the modem connectivity lights. Usually if a modem is connected to the internet, the connectivity light will be a steady or flickering green. Red  or no connectivity light almost always means no connection. It should be a matter of reflex to simply restart the modem and see if that fixes the problem.

– If the internet connectivity light doesn’t come back after restarting the modem, then call tech support.

– On rare occasions (1 out of 10), restarting the server plus the modem restored connectivity.

– Still no service? You can go get a cup of coffee then come back later and recheck.

– Or, if the internet connection light is green, try blowing away the browser cache and try to reload? Sometimes old versions of pages can stick in the cache.

– Can you load any other websites? If you can, then your particular server or service is most likely down.

– Can you ping the server? (for servers that allow ping). Determines if the server has basic connectivity.

– Can you run a tracert? Let’s you look at the connectivity between you and the remote server.

– Document the problems so you have a record for future reference.

– If you need continuous monitoring with alert thresholds, then look into evaluating continuous monitoring tools such as Paessler.

– If you know how to get the basic troubleshooting out of the way, or if you’ve already done it, then insist on escalation when you call tech support. You need to get back to coding as fast as possible.

OSCON 2012 Presentation – Mastering HTML5 Geolocation

Want a fast and fun learning experience on adding location to your web apps? I’ll be sharing practical tips on how to shave days or weeks off your learning curve. The session will cover the HTML5 Geolocation API, its benefits, how it works and what doesn’t work using real-world examples covering both desktop and mobile. If you are planning on attending OSCON 2012 stop by my session and say “hi”. My session is Location, Location, Location – Mastering HTML5 Geolocation, 1:40pm Thursday, July 19th in Portland 251.