End-to-end encryption and privacy controls.
Message and call for free* around the world.
Group conversations made simple.
Say it with stickers, voice, GIFs and more.
Reach your customers from anywhere.
https://9lib.co/document/ozln4kgq-AllIP網路預算為基礎之品質管理研究子計劃三無線區域網路之服務品質.html