A good portable speaker means music goes wherever she does without compromise on sound quality. These speakers need to be genuinely good at their job not just compact and cute. Look for speakers with solid battery life that can handle an afternoon in the garden or a weekend trip without dying halfway through. Waterproof or water-resistant construction matters if there is any chance of splashes or light rain. The best ones disappear into the background sonically speaking which means you forget you are listening to a small speaker and just listen to the music itself.