How can i improve the sound of Iphone 11?

I found a step-down trafo (2:1) improved the SQ of my Meizu phone. A bit bulky to carry around though.

"Have you thought about iPhone 11 > Apple Lightning to USB > AQ Dragonfly?"

This is a good possibility. Getting a  (Apple Lightning to USB) is easy enough, and the Dragonfly isnt big, but i never heard it and wonder if it will sound as good as the DX90.

Or if another mini dac would do better. A quick google search for "best portable dacs" revealed different reviewer opionions. No one agrees which is best - Cobalt, Audiolab M-DAC nano,  Clarus CODA USB DACm,  THX Onyx,  Maktar Spectra X2, etc.

Had a Dragonfly black. Sounded fine, especially when out in the noisy world. Sold it after I got the Questyle QP2r and never did an a/b comparison. Considering getting a cobalt for my desktop, which can serve double duty…

I used a cypher labs 720 dac with my iPhone and it sounded very good. I also used it between my Mac and desktop speakers

I prefer my Chord Hugo 2 but when I'm traveling light I love my AudioQuest Dragonfly Cobalt.  It delivers amazing sound in such a convenient small size.  I bought an AudioQuest Dragonfly Red when I misplaced my Cobalt and was surprised that an even more affordable DAC can sound so good.  The Cobalt has a lower noise floor, generally sounds better and is smaller in size, but the Red is really all you will need if you will be mainly using it in environments where you may hear some of the background sound.  After listening to both of them side-by-side I can easily hear that the Cobalt is clearer, more precise, has tighter deeper bass and more natural extended highs, a greater sense of depth and width to the soundstage, and an overall more pleasing sound than the Red. It really is worth the extra $100.