Nature calls regularly because I drink sufficient amounts of water, along with my morning coffee and my afternoon tea. If you're like me, your height is in your legs, so a low toilet seat plus bad knees or replaced hips can present a challenge.
When we first bought our house, we replaced the toilet in the en-suite bathroom for one that is taller. Including the toilet seat, my "throne" is a perfect-for-me eighteen inches in height, versus the standard height of fifteen inches.
Over the years, I've used several different models of portable, elevated toilet seats. My recommendation for you is to replace your existing toilet for one that is height-appropriate. I understand that it is not always possible to do so, but if you do, you'll notice that it is much easier to keep the standard toilet bowl clean.