The suction cup is wide and very good quality, it clings smoothly on my door glass shower. To recharge, just use the included cable to a USB socket, a full charge gives about ten hours of music. The Bluetooth pairing with my iPhone was made in seconds without any problems.
It is a small speaker and really convenient hands-free for the bathroom, not too big, nice and well finished, with sound quality quite good for its size and price. I recommend it.
[Sample provided in exchange for a fair comment]