So, following the advice on this SO post (sorry, I would comment there expect I don't have enough reputation)
Gradle: FAILURE: Could not determine which tasks to execute
I removed the tags from my .iml files, which allows me to compile. But when I go to run the .apk on a device, I get the error
"Error running TestProject: No Android facet found for TestProject"
Can someone help please, just want to get back to writing Android apps!
Add an android facet to your module by following below steps.
1) Go To File Menu -> Project Structure, or press (Ctrl+Alt+Shift+S) shortcut to open "Project Structure".
2) Select "Facets" which is under the "Project Settings" tab. (First column)
3) Click on "+" button which is at the top of the Second Column to add new facets.
4) Select "Android" facet from that "Add "menu which will prompt another dialog box to select a module. (Select a module to which you want to apply this facet).
5) Select your module and that's it. :)
Hope this will solve your problem.