There are physical limitations to a phone sensor that you just have to accept at some point. There is some fantastic software that makes the most out of these tiny sensors, but the tradeoff is loss of detail when you zoom in. You can improve your shooting technique, keep a clean lens, add third party lens attachments, but at the end of the day you can’t fight physics.

What’s your end goal? Are you looking to make prints? Share photos on social media?