Tuesday, May 10, 2011
Apps4Android: Developing accessibility apps for Android
By Steve Jacobs, President, IDEAL Group, Inc., and CEO, Apps4Android, Inc
This post is part of Who's at Google I/O, a series of guest blog posts written by developers who are appearing in the Developer Sandbox at Google I/O.
IDEAL Group's Android Development Team has developed and released several apps in the Android Market. In this post, we'll highlight three of our apps which capture some of the best aspects of developing on Android.
Android smartphones can have amazing hardware, and the platform gives developers the ability to tap into that power. Traditionally, handheld video magnifiers have been standalone, dedicated, hardware devices that can cost hundreds of dollars. Thanks to Android's Camera APIs, we're able to offer similar functionality in the form of a free, open source app.
In addition to using Android's zoom and flash features to make things easier for our users to see, we also enable our users to apply color effects such as converting everything to monochrome and even inverting the colors to improve contrast. Despite the wide variety of Android devices available, we found it relatively easy to support multiple devices since Android enables developers to check what the maximum zoom level is and what color effects are supported. Here's a YouTube video demonstrating IDEAL Magnifier in action.
IDEAL Item Identifier including Talking Barcode Maker
Thanks to Android's Intents system and its MediaRecorder and Text-To-Speech (TTS) APIs, we were able to produce an open source app which turns a user's phone into a talking barcode reader. Talking barcode readers enable blind and visually impaired users to scan the barcode of a product and hear what that item is. In addition, many of the higher end models offer the ability to let users create their own barcodes which they can stick onto items. Unfortunately, like video magnifiers, these devices have traditionally been quite expensive.
We solved the problem of detecting and reading barcodes without spending any development time by simply delegating this task to the ZXing Barcode Scanner. Once we get the UPC code of a product, we do a lookup of that UPC and speak the name of that product.
For custom labels, we record what the user is saying and save it to a file locally. We then use the Send Intent to enable users to email themselves a QR code which contains the automatically generated filename of that recording so that we play back that file when users scan this code. Users can print out the QR code on any sticky label, and voila, their very own custom label. Here's a video demonstrating IDEAL Item ID in action.
The Vista Center is a Palo Alto, California-based organization that helps the blind and visually impaired. We volunteered to create an Android app for them to help users access their educational materials which include topics such as how to use ticket machines and how to set up Android phones for accessibility.
This turned out to be a much easier project than expected, thanks to Android's accessibility features and the strong open source culture that is part of the Android platform's DNA. Specifically, we were able to take advantage of the Google Accessibility Team's I/O challenge which encouraged contestants to open source their submissions. We modified the ccTube app so that it always does a search on startup for videos from the Vista Center, and since Android has accessibility built right into the platform, we didn't need to do anything special to make it work with the TalkBack screen reader.
(Hat tip to Google's Charles L. Chen for helping us connect with the Vista Center and pointing us to Google I/O's Accessibility Challenge, and to Casey Burkhardt, who wrote ccTube and open sourced his code.)
Android is a tremendous platform for building tools that empower people. We're very excited by the fast pace of Android evolution and can't wait to see what the next iteration of this wonderful platform will have to offer.
Come see Apps4Android in the Developer Sandbox at Google I/O on May 10-11.
Steve Jacobs’ greatest passion is to enhance the independence, quality of life, education and mobile communications experiences for tens of millions of consumers with disabilities, senior citizens (like Steve), people who never learned to read, and everyone else.
Posted by Scott Knaster, Editor