The Anker Soundcore Motion 300 is good for outdoor use. This small, lightweight speaker is easy to bring with you, and you can strap it to a bag or backpack as you travel around. It's solid and sturdy, with an IPX7 rating for water resistance. It's designed so you can switch up its orientation based on what's convenient to you, and the speaker adjusts its output accordingly for the best possible sound. It still gets pretty loud for a small speaker, although there's some compression as you push it to max volume.