I cite the article by Hans Radder entitled "Everything of value is useful: How philosophy can be socially relevant", published by Social Epistemology Review and Reply Collective. He concludes that many social, scientific, and personal issues can benefit from philosophy. (This question is not about the benefits of studying philosophy).
I think especially in the realms of the personal, but also in the social and scientific as you've said.
For a start, being a theist and Catholic, I will of course have to point to how Aristotle lead to Thomism, and how Thomistic scholasticism ushered in a golden age of reason within the Church that has enormously benefitted society.
However, I'd like to make a personal note here, precisely on the point of personal (and the resultant social) benefit of philosophy for the layman.
A (very) personal note
We live in a tremendously polarised and combative age. We live in a world where everyone has to pretend they know exactly what's going on.
Philosophy, done right, in the spirit not of self-aggrandisement or politicking, but in a spirit of absolute truth seeking, should have one, beautiful, potent impact on any mind truly willing to engage with it; humility.
Cogito, ergo sum. When truly pursuing philosophy, many of us come to the simple realisation that we all have next to no idea what's actually going on.
We're all in the dark. We can explore possibilities and theories, but we can't know the truth, at least not fully and not in this life.
When we realise this, and when we truly realise that this holds for all mankind, we can perhaps begin to find some empathy for one another. We're all in this together, one great, very confused mass.
Only when we stop believing we have all the answers can we stop and listen, in the hope than someone else might have but one.
The question refers to the essay Everything of value is useful: How philosophy can be socially relevant by the contemporary philosopher Hans Radder.
Radders main thesis
As a discipline, philosophy is useful if it makes a valuable contribution to social, scientific or personal reflection.
One can read this statement as objecting that philosophy per se has a value. Instead, the author argues for bringing philosophy into current discussions about questions from daily life.
Radder's examples have quite different weight: Who is the mother in case of surrogate motherhood? Should patenting of plants, animals and humans be allowed? How philosophers of language can improve the storyline in computer games.
IMO, concerning the task to decide practical questions of daily life philosophy can contribute with its specific expertise only in interdisciplinary teams. Working together with experts from other social groups.
But that’s not so remarkable. Because these other disciplines have long ago been outsourced from philosophy, and then made their specific progress.
What is useful to one person might be useless to another. So my reading of the question is: "Can philosophy be useful to me?"
Generally, when someone asks this question, it is because one doesn't personally see the value of philosophy in one's own life.
And that is fine.
For some, philosophy is just a game like chess or sudoku, something unapplicable in real life. For instance, a person might muse that she doesn't go by the correspondence theory of truth, for she likes the sound of that on a philosophy forum, but would still use "true" in the sense of "corresponding to facts" in day to day life. For her, philosophy is a pastime, about as useful as crosswords.
For others it's a job, something serious that they are paid to do, not necessarily a life changer but a life earner. For them, coming to sharp conclusions too quickly might be problematic, because then the job is technically "done" and so their services might no longer be required. Professional philosophers are thus more likely to appreciate the endless, never-finished aspects of philosophy than amateurs, who might feel impatient with it.
I see a third category for whom the utility of philosophy is starkly different: those amateurs (and professionals) who are drawn to philosophy by a call, a question or a "cry" as Deleuze put it. For them philosophy is a fight against anguish, an effort to find reasons for stuff that may look highly unreasonable, an attempt to answer a devoring question mark.
Those philosophers are searching for something important to them. They are not just musing with words: they have a problem to solve.
If you don't see yourself as part of the latter category, then your life is blessed and you probably don't need philosophy.
Philosophy explores the fundamental questions of the human condition.
What are we? Why are we here? What can we know about ourselves and about our surroundings? How do we think at all, how can we reason properly? How can we tell good from bad, false from true, beauty from ugliness? What is love? How should we conduct ourselves? What should we strive for?
Most of these questions cannot be answered finally and conclusively, or there are competing claims to such answers. But these are the questions which matter.
Everybody, I hope, has asked themselves some of these questions or discussed them with others. We may not always realize that as "philosophy", but it is.
By contrast, questions typically considered useful like "How can I get rich quickly?" or "What is the cheapest flight to Houston for Christmas?" are trivial, meaningless and hollow if we never think about the fundamental questions above.
Philosophy is not only useful, it is indispensable.
Philosophy plays in the humanities and social studies essentially the same role that logic, mathematics, formal systems and notation play in the exact sciences — the role of a research language for expressing ideas and results.
Namely: it develops ways of reasoning, assessing and making decisions necessary here and now, in the face of a lack of specific and/or sufficiently substantiated information about the situation and what is really happening. This allows to achieve semi-intuitively, which is fundamentally impossible in exact sciences based on experiment and its measurements in objective terms.
Thus, all arts (including design), all politics (including law, sociology and economics), all literature and all education are directly based on philosophy to one degree or another. It's that easy.
Maybe one of the uses of philosophy (as an area of study, i.e. concentrated efforts) is decreasing load of philosophical (i.e. effectively unanswerable) questions on other areas, such as science or religion?
If you remove formal, organised philosophy (i.e. philosophy books, philosophers, study of philosophy in universities), then maybe maths, phyiscs, linguistics and maybe just common ordinary life can become more riddled with philosophical questions, without people realising that those questions are special and spending time to answer them instead of concentrating on more practical matters?