Can someone else track my phone without me knowing?

Could you please elaborate on the possibility of someone tracking my phone without my consent or knowledge? Is it feasible for a third party to access my phone's location or other sensitive data surreptitiously? Are there any telltale signs that would indicate my phone is being tracked? What are the potential risks associated with such tracking, and how can I safeguard myself against it? Is there any software or application that can help me detect and prevent unauthorized tracking? Thank you for addressing these concerns.