Extending android built in apps

Question

I have been messing around with android programming for the last couple of months, now after developing a couple of apps I would like to extend exisiting android app so that I can change their menues add more features etc. for that I have two questions: 1. Can i upload such a "driver" to the android market as an app? even after it gets installed all it do is add more features to the android OS? 2. where can I get more info about how and what should I read\learn for my purpose?

Tnx in advance.

Answer 1

if you want to make certain expansions to system apps, well... it's difficult. You will have to do that by editing the system app and adding new smali code for functionality. The problem is, that it will work only on your phone, on or phones with the exact system. For example, if you want to add new functionality to Phone.apk from a samsung phone, the resulting app will work only on samsung phones that have an identical Phone.apk. Besides, the phone must be rooted and the installation can't be done from Play... because it can't replace a system app.

One other thing to consider, for replacing functionality inside apps is Xposed Framework

You can read more about that, there.

In conclusion, it's not easy or pleasant to waste your time expanding system apps. You can try to develop new mods for CM for example.