Helm Audio's $99 Bolt DAC is the easiest way to get better audio out of your phone

Helm Audio's Bolt is a $99 portable DAC/amp that allows you to plug in your favorite wired audio gear to your phone and stream hi-res music. Thanks to MQA decoding, you can use this DAC to stream Tidal Masters on the go.

source https://www.androidcentral.com/accessories/audio/helm-audio-bolt-dac-review