I\'m designing an android app which will need to do the following steps:
The choice is mainly dependent on the app design. Since both AsyncTask and IntentService stands their ground, what you may want from the app(user experience) is more important and then choose either or both. Some scenarios are mentioned below (mostly what I experienced while developing apps)
Assume apps that have feeds pages - where more than one api calls are made to make the page presentable ( /getFriends, /getDates, /getPictures etc.) you can warp all such api calls to a single AsyncTask with executor which is multithreaded and the sequence of execution doesn't matter. In contrast to IntentService which runs all calls in sequence in a single worker thread. For a high end device with multi-core the call from AsyncTask is more effective. And if you start the AsyncTask on UI thread then updating IU is a piece of cakes(read less boiler plate code). And even if an user leaves the page, with intelligent use of not holding on to the context the app doesn't crash.
Assuming you are trying to write an app which doesn't need the user to be on view/activity/fragment and the total execution time to show something is not mission critical (assume sync service or user notification/alarm) then IntentService is a better choice. (no hassle to start Asynctask on UI thread so that you don't need to write a Handler to force changes on UI etc. etc. and less boiler plate code)
From my experience - write small app for both and compare the pros and cons to get a better idea. (p.s I'd suggest take a look at the iosched app from google to get a better idea - they use both Asynctask and IntentService)