A recap about the progress I've done so far on my first Android app (Update 1 here).
After spending some time getting the visual layout done (or making it look ok on a screen), I've finally started playing around with actual code that does stuff. Android's developer's site is pretty good as a reference, although sometimes examples are lacking or simply not the complete thing to make it work with something else etc… I've had to rely a bit on external sources especially with stuff to communicate with a server (POST requests, response). Stackoverflow is amazing .
The first thing I implemented was the actual settings page where the user needs to enter their account number, password and phone number. These values were successfully stored using the SharedPreferences interface (not shared with other apps of course !). Next was getting the user's balance in their account (specified in the settings). The first time I implemented it without an AsyncTask, as the refreshing was occurring the application would appear as if it were hanging (but eventually show the balance). Adding that operation as an AsyncTask, plus a ProgressDialog made things work and look better. Last thing was making SMS work, and lo and behold it worked ! I tried to get contacts selection implemented and was only successful getting the list but once a user selects the contact, the number is not sent back to the SMS activity. I am thinking of adding one more feature, getting history of stuff (calls/SMS) as seen by the VoIP provider so that users can see how much their last few calls cost and so on.
Things are way beyond complete and I have to decided to take things one step at a time. I tend to get frustrated when things don't work as intended and take a day (or a few ) off coding and start with a clear mind.