Allow android app to be installed on external storage

[1000283]

Feature request

Description

Allow android app to be installed on external storage.

Describe the solution you'd like

Allow android app to be installed on external storage.

Describe alternatives you've considered

None. My phone isn't rooted and has "only" 4GB internal memory, which has been progressively hogged by the system over time. I move all apps i can to external storage SDCard but quite a few don't allow this. I know it's not just a matter of changing the manifest: on certain conditions external storage gets unmounted. Still, i'd very much prefer to move apps to external storage whenever possible.