I'm considering creating a screen reader for Android. My questions are as follows. One how much of the internals of Android are exposed through the Java API? I'm looking for things such as system wide notification when text is displayed, notification of a new application being launched, etc. I'd rather not have to modify the kernel source and only allow my app to run on a developer phone. Two, how much processor and memory are left over on the G1 assuming no applications running? Three assuming average use of applications on the phone how much processor and memory are left?
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I'm aware that applications should not be designed to work on a specific phone. I picked the G1 because it's the most popular phone currently running Android that I know of. I am looking for lower end system specs that my program would have to fit in, it may run great on a netbook with Android installed but use to much memory and processor to run on most Android handsets.
Update:
There are now two screen reader projects that use Android 1.6, they can be found at
http://google-opensource.blogspot.com/2009/10/talkback-open-source-screenreader-for.html
http://spiel.thewordnerd.info/