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.
http://powerpoint.farafile.ir/file/28516/تحقیق-استراتژي-هاي-شتاب-و-معكوس-با-استفاده-از-اثر-تقدم-تاخر