Android web app x other devices web app

[Phelipe Maia]

My question from a beginner android user... What is the difference between a development of android web app and other devices web app? For example: If I develop a web app for android I can access from other devices, can't I? So, Why a book specifically for android?

[Perry Hoekstra]

Define other devices? Android-based devices is a yes. iPhone, Windows Mobile, or Blackberry is a no.

[Phelipe Maia]

Perry Hoekstra wrote:Define other devices? Android-based devices is a yes. iPhone, Windows Mobile, or Blackberry is a no.

Sorry, other devices = other o.s.. What is the particularity of android web app? Why i can't access from iPhone, Windows Mobile, or Blackberry? My question it's because if I develop a web app, doesn't matter the agent, I will access from anyone OS...

Thanks...

[Damon Oehlman]

Hey Phelipe,

Thanks for the question. I think it is probably one of the best questions that anyone can ask before buying either this book, or any book on cross-platform (or device) mobile development.

It really comes down to the 80/20 rule (as so many things do). Essentially, 80% (and sometimes more, depending on what you are doing) of the code you write will work on any mobile device that comes with a WebKit browser, but the device OSes do require slightly different treatment for programming for the mobile web. Additionally, one of the things that I like to keep as an option is packaging an application for native distribution, which technologies like PhoneGap make possible.

I think that for now, an Android Web Apps book makes sense, but less so in a few years time when mobile web app programming has matured and starts to become the preferred approach - well, that's my prediction anyway.

The good news is that the majority of the books content is applicable to programming for other mobile device platforms that ship with WebKit browsers (iOS, WebOS, Blackberry Torch, some Nokia), but this still leaves a lot of devices that code samples in the book just won't work on. For example, Windows Phone7 as it ships with a browser roughly equivalent to IE7 (so no HTML5 or CSS3 support). As I said, this will almost certainly change in time, and when it does, then having a book titled "Pro Mobile Web Apps" (or similar) makes sense and will be able to provide content that someone buying the book would probably expect.

I hope this answers your question, but if not, I'll definitely try and provide more info.

Cheers,
Damon.

[Tiffany Coleman]

The good news is that the majority of the books content is applicable to programming for other mobile device platforms that ship with WebKit browsers (iOS, WebOS, Blackberry Torch, some Nokia), but this still leaves a lot of devices that code samples in the book just won't work on.

Does that mean that this book will help me be able to write an app that I can use on my droid, as well as, then be able to turn around and use it on my iPad? Most of my app ideas are for things like -- accessing online games or reviewing specific database information for online games. I'd like to be able to do it whether I was using my phone or my tablet.

And -- will the book give me enough of the 80% that I could learn the 80% and then grab the 20% to make my app work cross platform? Does it define the 80/20 items -- for instance, does it say, this portion will work multi-platform and also say, this is Android specific and doesn't function somewhere else? If not, would it then be "trial and error" to find out which parts work and don't work if you want to have it be cross OS?

Thanks.

--tiffany

[Phelipe Maia]

Damon Oehlman wrote:Hey Phelipe,

Thanks for the question. I think it is probably one of the best questions that anyone can ask before buying either this book, or any book on cross-platform (or device) mobile development.

It really comes down to the 80/20 rule (as so many things do). Essentially, 80% (and sometimes more, depending on what you are doing) of the code you write will work on any mobile device that comes with a WebKit browser, but the device OSes do require slightly different treatment for programming for the mobile web. Additionally, one of the things that I like to keep as an option is packaging an application for native distribution, which technologies like PhoneGap make possible.

I think that for now, an Android Web Apps book makes sense, but less so in a few years time when mobile web app programming has matured and starts to become the preferred approach - well, that's my prediction anyway.

The good news is that the majority of the books content is applicable to programming for other mobile device platforms that ship with WebKit browsers (iOS, WebOS, Blackberry Torch, some Nokia), but this still leaves a lot of devices that code samples in the book just won't work on. For example, Windows Phone7 as it ships with a browser roughly equivalent to IE7 (so no HTML5 or CSS3 support). As I said, this will almost certainly change in time, and when it does, then having a book titled "Pro Mobile Web Apps" (or similar) makes sense and will be able to provide content that someone buying the book would probably expect.

I hope this answers your question, but if not, I'll definitely try and provide more info.

Cheers,
Damon.

Perfect answer... Thank you so much!!!

[Damon Oehlman]

Tiffany Coleman wrote:

The good news is that the majority of the books content is applicable to programming for other mobile device platforms that ship with WebKit browsers (iOS, WebOS, Blackberry Torch, some Nokia), but this still leaves a lot of devices that code samples in the book just won't work on.

Does that mean that this book will help me be able to write an app that I can use on my droid, as well as, then be able to turn around and use it on my iPad? Most of my app ideas are for things like -- accessing online games or reviewing specific database information for online games. I'd like to be able to do it whether I was using my phone or my tablet.

And -- will the book give me enough of the 80% that I could learn the 80% and then grab the 20% to make my app work cross platform? Does it define the 80/20 items -- for instance, does it say, this portion will work multi-platform and also say, this is Android specific and doesn't function somewhere else? If not, would it then be "trial and error" to find out which parts work and don't work if you want to have it be cross OS?

Thanks.

--tiffany

Hey Tiffany,

Another good question. The short answer is yes. Because both your Droid and an iPad (I have a HTC Desire and iPad) both have a Webkit browser just about everything you will code will "just work". I'd recommend starting by targeting the Android first as it's probably the "fussier" of the two platforms.

The one thing you should consider when writing for these two platforms is the different screen sizes that you are coding for. So when thinking about your layout think about using percentages rather than absolute pixel dimensions to ease the transition, but you can also use CSS3 media queries to supply different styles for the different screen sizes also.

In terms of what to watch out for, main things are slight variations in Touch handling and some frustrating things around Android 2.1's handling of "device-dpi" when working with the HTML canvas (problem goes away in 2.2 thankfully). On the touch handling front, I have written a Javascript library to try and help out with that, but it isn't covered in the book as I only created it very recently.

Hope that helps answer your question.

Cheers,
Damon.