  The existence of solitons -- stable, long-lived, and localized field
configurations -- is a generic prediction for ultralight dark matter. These
solitons, known by various names such as boson stars, axion stars, oscillons,
and Q-balls depending on the context, are typically treated as distinct
entities in the literature. This study aims to provide a unified perspective on
these solitonic objects for real or complex, scalar or vector dark matter,
considering self-interactions and nonminimal gravitational interactions. We
demonstrate that these solitons share universal nonrelativistic properties,
such as conserved charges, mass-radius relations, stability and profiles.
Without accounting for alternative interactions or relativistic effects,
distinguishing between real and complex scalar dark matter is challenging.
However, self-interactions differentiate real and complex vector dark matter
due to their different dependencies on the macroscopic spin density of dark
matter waves. Furthermore, gradient-dependent nonminimal gravitational
interactions impose an upper bound on soliton amplitudes, influencing their
mass distribution and phenomenology in the present-day universe.
