We consider a lower weight better because lighter devices are more comfortable to carry. A lower weight is also an advantage for home appliances, as it makes transportation easier, and for many other types of products.
The first number of the IP rating refers to protection against dust, while the second number refers to protection against liquid. E.g. a first number of 6 denotes that it is completely dustproof, and a second number of 7 denotes that the device can withstand full immersion in water.
This type of device allows you to listen at lower volume levels, causing less ear fatigue as you don't have to crank up the volume to overcome background noise. Ideal for plane rides and morning commutes.
aptX Lossless is an audio codec for Bluetooth devices that is developed by Qualcomm. It supports high quality 16-bit/44.1kHz audio (at a maximum bit rate of 1200kbps). This codec provides CD-quality audio without any loss of data.
Ambient sound mode uses microphones to pass through ambient noises so that they can still be heard. It’s useful when you want to listen to music but also be aware of what’s happening around you, for example when you’re jogging but still want to be able to hear traffic.