Originally Posted by
PJRed2008 That will work to clear one you don't want, not one you do.
If you were to install,.. Let's say QuikPic, and inside an application, say Facebook, you wanted to upload a picture. You click on it, and instead of going straight to the gallery, Android would give you an option to either choose QuikPic, or your gallery, asking with the action of only choosing that option once, or setting it as the default application to open when doing the predefined action.
So, you choose the gallery, and pick the option always, so it is set as the default application to open, when choosing to upload a picture on Facebook.
Say you explore QuikPic, and find that you like it's functionality better, than the stock gallery application. You would go to the gallery application page, under the apps tab in your settings, and scroll down to the option 'clear defaults'. In clearing this, you clear the application of any default preference on actions that call upon the gallery for function.
Say you go to Facebook to upload another picture, and when you click the button to upload, you will not be taken to the gallery, but instead be offered to choose between QuikPic, or your gallery. If you choose QuikPic, then select 'always', any function that calls upon the gallery, will instead lead you to be redirected to QuickPic instead.
This will only happen, if you have two applications that perform the same function, such as launchers, lock screen replacements, etc..,
I hope that clears up any confusion you might have had, concerning what I previously stated.
Tapped from my Nexus 10.1