I put the larger 6.5" version of
these Pyle bluetooth outdoor speakers out by my pool almost two years ago, and (despite the lackluster Amazon reviews) they've been perfect for me. They apparently get waaaay too loud for my elderly Russian neighbor lady, but other than that I've had no issues. Easy install, control volume and everything from your phone or we sometimes will bring an Echo Dot out, and they've paired easily with everything.
Before I got those, I bought a couple
UE Wonderbooms as a temp solution. They worked awesome paired up, and they're still great now doing duty while camping, at the beach, etc.