It depends.
Choose singletons, because:
- In general, I'd say a singleton is slightly neater because it allows you to do some initialization of the singleton object in/from the (private) constructor.
- When it is later decided this object should no longer be a singleton (due to new insights or new requirements), it is easier to refactor it: you just need to change all the places that get the instance, instead of all calls to the static methods.
Use static methods, because:
- In the specific case of android, you might prefer static methods for performance - I suspect calling a static function might be a bit faster (easier to optimize for the compiler) compared to calling a method on a singleton object.
